Mobile device

Abstract

A movable device (13) comprises: a movable unit (103) including a reflector (102) configured to reflect light; a support portion (104a, 104b) including a first end and a second end, the first end being connected to the movable unit, the support portion being configured to swingably support the movable unit; and a fixed unit (108) connected to the second end of the support portion, wherein the support portion comprises a plurality of beam units (115) and a connecting unit (116) connecting adjacent beam units among the plurality of beam units, wherein when the support portion is divided into two parts at a predetermined or given position, and the two parts include a first part closer to the fixed unit and a second part closer to the movable unit, the beam units among the plurality of beam units in the first part have higher rigidity than the beam units among the plurality of beam units in the second part, and the beam units among the plurality of beam units in the second part are longer than the beam units among the plurality of beam units in the first part.

Description

Technical Field

[0001] Embodiments described herein relate to a mobile device. Background Art

[0002] In recent years, with the development of micro-machining technology to which semiconductor manufacturing technology is applied, the development of micro-electromechanical systems (MEMS) produced by micro-fabrication of silicon and glass has progressed.

[0003] For example, one example of a known MEMS device includes a movable device obtained by forming a movable unit having a reflective surface and an elastic beam on a wafer, wherein a drive beam constructed by stacking a thin piezoelectric material on the elastic beam is configured to drive (rotate) the movable unit (see, for example, PTL 1).

[0004] It is known that a two-dimensional optical deflecting device and an image display device using the same are implemented using such a movable device. Summary of the invention

[0005] Technical issues

[0006] In order to improve the mechanical drive sensitivity and obtain a large scanning angle using an optical deflector (an example of such a movable device), it is conceivable to increase the length of a beam unit used as a vibration beam included in a zigzag structure. However, when the length of the beam unit used as a vibration beam is increased, there is a problem that the natural resonance frequency of the entire actuator is reduced. Therefore, the mechanical strength is reduced, and jitter is likely to occur.

[0007] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide a movable device capable of alleviating a decrease in a natural resonance frequency and achieving a large scanning angle.

[0008] Solution to the problem

[0009] A mobile device according to one aspect of the present disclosure includes:

[0010] a movable unit including a reflector configured to reflect light;

[0011] a support portion including a first end and a second end, the first end being connected to the movable unit, and the support portion being configured to swingably support the movable unit; and

[0012] a fixing unit connected to the second end of the supporting portion,

[0013] The support portion comprises:

[0014] multiple beam elements; and

[0015] at least one connecting unit connecting adjacent beam units of the plurality of beam units,

[0016] Wherein, in the case where the support portion is divided into two parts at a predetermined or given position, and the two parts include a first part closer to the fixed unit and a second part closer to the movable unit,

[0017] Among the plurality of beam elements, the beam elements in the first portion have higher stiffness than the beam elements in the second portion, and

[0018] The beam elements in the second portion are longer than the beam elements in the first portion.

[0019] Beneficial effects of the present invention

[0020] With the movable device according to the disclosed technology, the reduction of the natural resonance frequency can be alleviated, and a large scanning angle can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram showing an optical scanning system;

[0022] Figure 2 It is the hardware configuration diagram of the optical scanning system;

[0023] Figure 3 is a functional block diagram of the control device;

[0024] Figure 4 is a flow chart of an example of a process of an optical scanning system;

[0025] Figure 5 is a schematic diagram of a car provided with a head-up display device;

[0026] Figure 6 is a schematic diagram of a head-up display device;

[0027] Figure 7 is a schematic diagram of an imaging device provided with an optical writing device;

[0028] Figure 8 is a schematic diagram of an optical writing device;

[0029] Fig. 9 is a schematic diagram of a car equipped with a LiDAR device;

[0030] Fig.10 is a schematic diagram of a LiDAR device;

[0031] Fig.11 It is a schematic diagram of the structure of the laser headlight;

[0032] Fig.12is a schematic diagram showing an example of a head mounted display;

[0033] Fig.13 is a schematic diagram showing an example of a partial configuration of a head mounted display;

[0034] Fig.14 It is a schematic diagram of the packaged movable device;

[0035] Fig.15 is a plan view of a single-axis light deflector;

[0036] Fig.16 It is along Fig.15 A cross-sectional view taken along the dotted line 15A-15B;

[0037] Fig.17 is a plan view of a two-end-supported optical deflector;

[0038] Fig.18 is a plan view of a light deflector according to a first embodiment;

[0039] Fig.19 is a cross-sectional view of a light deflector according to a first embodiment;

[0040] Fig. 20 is a characteristic diagram of the light deflector according to the first embodiment;

[0041] Fig.21 is a plan view of a light deflector according to a variation of the first embodiment;

[0042] Fig. 22 is a plan view of a light deflector according to a variation of the first embodiment;

[0043] Fig.23 is a plan view of a light deflector according to a variation of the first embodiment;

[0044] Fig.24 is a plan view of a light deflector including a single supporting portion according to a variation of the first embodiment;

[0045] Fig.25 is a plan view of a light deflector including three supporting portions according to a variation of the first embodiment;

[0046] Fig.26 is a plan view of a light deflector including four supporting portions according to a variation of the first embodiment;

[0047] Fig. 27 is a plan view of a light deflector according to a variation of the first embodiment;

[0048] Fig.28is a plan view of a light deflector according to a variation of the first embodiment;

[0049] Fig.29 It is along Fig.28 A cross-sectional view taken along the dotted line 28A-28B;

[0050] Fig.30 It is along Fig.28 A cross-sectional view taken along the dotted line 28C-28D;

[0051] Fig.31 is a plan view of a light deflector according to a variation of the first embodiment;

[0052] Fig.32 is a plan view of a light deflector according to a variation of the first embodiment;

[0053] Fig.33 is a plan view of a light deflector according to a second embodiment;

[0054] Fig.34 It is along Fig.33 A cross-sectional view taken along the dotted line 18A-18B;

[0055] Fig.35 is a characteristic diagram of the light deflector according to the second embodiment;

[0056] Fig.36 is a plan view of a light deflector according to a variation of the second embodiment;

[0057] Fig.37 is a plan view of a light deflector according to a variation of the second embodiment;

[0058] Fig.38 is a plan view of a light deflector according to a variation of the second embodiment;

[0059] Fig.39 is a plan view of a light deflector according to a variation of the second embodiment;

[0060] Fig.40 is a plan view of a light deflector according to a variation of the second embodiment;

[0061] Fig.41 is a plan view of a light deflector according to a variation of the second embodiment;

[0062] Fig.42 is a plan view of a light deflector including a single supporting portion according to a variation of the second embodiment;

[0063] Fig.43is a plan view of a light deflector including three supporting portions according to a variation of the second embodiment;

[0064] Fig.44 is a plan view of a light deflector including four supporting portions according to a variation of the second embodiment;

[0065] Fig.45 is a plan view of a light deflector according to a variation of the second embodiment;

[0066] Fig.46 is a plan view of a light deflector according to a variation of the second embodiment;

[0067] Fig.47 It is along Fig.46 A cross-sectional view taken along the dotted line 31A-31B;

[0068] Fig.48 It is along Fig.46 A cross-sectional view taken along the dashed line 31C-31D;

[0069] Fig.49 is a schematic diagram of a connection unit having different curvature radii at a corner according to a variation of the second embodiment;

[0070] Fig.50 is a plan view of a light deflector according to a variation of the second embodiment;

[0071] Fig.51 is a plan view of a light deflector according to a variation of the second embodiment;

[0072] Fig.52 is a plan view of a light deflector according to a third embodiment;

[0073] Fig.53 It is along Fig.52 A cross-sectional view taken along the dotted line 4A-4B;

[0074] Fig.54 is a characteristic diagram of the light deflector according to the third embodiment;

[0075] Fig.55 is a plan view of a light deflector according to a variation of the third embodiment;

[0076] Fig.56 is a plan view of a light deflector according to a variation of the third embodiment;

[0077] Fig.57 is a plan view of a light deflector according to a variation of the third embodiment;

[0078] Fig.58is a plan view of a light deflector according to a variation of the third embodiment;

[0079] Fig.59 is a plan view of a light deflector according to a variation of the third embodiment;

[0080] Fig.60 is a plan view of a light deflector according to a variation of the third embodiment;

[0081] Fig.61 is a plan view of a light deflector including three supporting portions according to a variation of the third embodiment;

[0082] Fig.62 is a plan view of a light deflector including four supporting portions according to a variation of the third embodiment;

[0083] Fig.63 is a plan view of a light deflector according to a variation of the third embodiment;

[0084] Fig.64 is a plan view of a light deflector according to a variation of the third embodiment;

[0085] Fig.65 It is along Fig.64 A cross-sectional view taken along the dotted line 16A-16B;

[0086] Fig.66 It is along Fig.64 A cross-sectional view taken along the dotted line 16C-16D;

[0087] Fig.67 is a plan view of a light deflector according to a variation of the third embodiment; and

[0088] Fig.68 is a plan view of a light deflector according to a variation of the third embodiment. DETAILED DESCRIPTION

[0089] Hereinafter, embodiments of the present disclosure will be described in detail.

[0090] <Optical Scanning System>

[0091] First, refer to Figures 1 to 4 The optical scanning system including the movable device of this embodiment is described in detail.

[0092] Figure 1 is a schematic diagram showing an example of an optical scanning system. Figure 1As shown, the optical scanning system 10 is a system for optically scanning a scanning surface 15 by deflecting light emitted from a light source device 12 by a reflection surface 14 of a movable device 13 according to control of a control device 11 .

[0093] The optical scanning system 10 includes a control device 11 , a light source device 12 , and a movable device 13 including a reflective surface 14 .

[0094] The control device 11 is a circuit unit including, for example, a central processing unit (CPU), a field programmable gate array (FPGA), etc. For example, the movable device 13 includes a reflective surface 14 and is a micro-electromechanical system (MEMS) device capable of moving the reflective surface 14. For example, the light source device 12 is a laser device that emits laser light. For example, the scanning surface 15 is a screen.

[0095] The control device 11 generates a control instruction for the light source device 12 and the movable device 13 according to the obtained optical scanning information, and outputs a driving signal to the light source device 12 and the movable device 13 according to the control instruction.

[0096] The light source device 12 emits light according to the received driving signal. The movable device 13 moves the reflecting surface 14 in a single axial direction or in two axial directions according to the received driving signal.

[0097] Thus, for example, by the control performed by the control device 11 based on the image information (i.e., an example of optical scanning information), the reflection surface 14 of the movable device 13 is reciprocated within a predetermined range in two axial directions, and the light emitted from the light source device 12 to be incident on the reflection surface 14 is deflected and optically scanned around a given single axis, so that any given image can be projected onto the scanning surface 15. The details of the movable device of this embodiment and the details of the control of the control device will be described later.

[0098] The following will refer to Figure 2 A hardware configuration of one example of the optical scanning system 10 is described. Figure 2 FIG. 1 is a hardware configuration diagram of an example of the optical scanning system 10. Figure 2 As shown, the optical scanning system 10 includes a control device 11, a light source device 12 and a movable device 13 which are electrically connected to each other. The control device 11 includes a CPU 20, a random access memory (RAM) 21, a read-only memory (ROM) 22, an FPGA 23, an external interface 24, a light source device driver 25 and a movable device driver 26.

[0099] The CPU 20 is an arithmetic processing device that implements overall control and functions of the control device 11 by reading programs and data from a storage device (eg, the ROM 22 or the like) into the RAM 21 and processing them.

[0100] The RAM 21 is a volatile storage device that temporarily stores programs and data.

[0101] The ROM 22 is a nonvolatile storage device that retains programs and data even when the power is turned off, and it stores processing programs and data that the CPU 20 executes to control the functions of the optical scanning system 10 .

[0102] The FPGA 23 is a circuit for outputting control signals suitable for the light source device driver 25 and the movable device driver 26 according to the processing of the CPU 20 .

[0103] For example, the external interface 24 is an interface for communicating with an external device, a network, etc. Examples of external devices include a host device (e.g., a PC (personal computer)) and a storage device (e.g., a USB memory, an SD card, a CD, a DVD, a HDD, a SSD, etc.). Examples of networks include a CAN (controller area network) of a car, a LAN (local area network), the Internet, etc. The external interface 24 may be configured to be able to connect or communicate with an external device, and a dedicated external interface 24 may be provided for each external device.

[0104] The light source device driver 25 is a circuit that outputs a drive signal (for example, a drive voltage) to the light source device 12 according to the received control signal.

[0105] The movable device driver 26 is a circuit that outputs a drive signal (eg, a drive voltage) to the movable device 13 according to the received control signal.

[0106] In the control device 11, the CPU 20 obtains the optical scanning information from the external device or the network via the external interface 24. The control device 11 may be configured so that the CPU 20 obtains the optical scanning information. For example, the optical scanning information may be stored in the ROM 22 and the FPGA 23 in the control device 11. Alternatively, a storage device (e.g., SSD) may be provided in the control device 11, and the optical scanning information may be configured to be stored in the storage device.

[0107] In this case, the optical scanning information is information indicating how to optically scan the scanning surface 15. For example, in the case of displaying an image by optical scanning, the optical scanning information is image data. For example, in the case of optical writing by optical scanning, the optical scanning information is writing data indicating a writing order and a writing position. For example, in the case of object recognition by optical scanning, the optical scanning information is light emission data indicating a light emission timing and a light emission range for light emission in order to recognize an object.

[0108] The control device 11 can use the instructions of the CPU 20 and Figure 2 The shown hardware configuration realizes the functional configuration described hereinafter.

[0109] The following will refer to Figure 3 The functional configuration of the control device 11 of the optical scanning system 10 is described. Figure 3 1 is a functional block diagram of an example of the control device 11 of the optical scanning system 10 .

[0110] like Figure 3 As shown, the control device 11 includes a control unit 30 and a drive signal output unit 31 as functional components.

[0111] For example, the control unit 30 is implemented by the CPU 20, the FPGA 23, etc. The control unit 30 obtains optical scanning information from an external device, converts the optical scanning information into a control signal, and outputs the converted control signal to the drive signal output unit 31. For example, the control unit 30 obtains image data as optical scanning information from an external device, etc., generates a control signal from the image data by performing a predetermined process, and outputs the generated control signal to the drive signal output unit 31. The drive signal output unit 31 is implemented by the light source device driver 25, the movable device driver 26, etc. The drive signal output unit 31 outputs a drive signal to the light source device 12 or the movable device 13 according to the received control signal.

[0112] The driving 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, the driving signal is a driving voltage for controlling the light emission timing and light emission intensity of the light source. For example, in the movable device 13, the driving signal is a driving voltage for controlling the timing of movement and the movable range of the reflecting surface 14 of the movable device 13.

[0113] The following will refer to Figure 4 A process of optically scanning the scanning surface 15 by the optical scanning system 10 will be described. Figure 4 is a flow chart of an example of the processing of the optical scanning system.

[0114] In step S11 , the control unit 30 obtains optical scanning information from an external device or the like.

[0115] In step S12 , the control unit 30 generates a control signal according to the obtained optical scanning information, and outputs the generated control signal to the driving signal output unit 31 .

[0116] In step S13 , the driving signal output unit 31 outputs a driving signal to the light source device 12 and the movable device 13 according to the received control signal.

[0117] In step 14, the light source device 12 emits light according to the received driving signal. In addition, the movable device 13 moves the reflecting surface 14 according to the received driving signal. With the operation of the light source device 12 and the movable device 13, the light is deflected in any given direction and optical scanning is performed.

[0118] In the optical scanning system 10 of this embodiment, the control device 11 has the function of controlling both the light source device 12 and the movable device 13, but a control device for the light source device 12 and a control device for the movable device 13 may be separately provided.

[0119] In the above-mentioned optical scanning system 10, the control device 11 includes 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, but these functions may be provided in separate devices. For example, the drive signal output device having the drive signal output unit 31 may be provided separately from the control device 11 having the control unit 30. In the optical scanning system 10, the optical deflection system for deflecting light may be composed of the control device 11 and the movable device 13 having the reflective surface 14.

[0120] <Image Projection Device>

[0121] The following will refer to Figure 5 and Figure 6 The image projection device including the mobile device of this embodiment will be described in detail.

[0122] Figure 5 is a schematic diagram of a car 400 provided with a head-up display device 500. The head-up display device 500 is an example of an image projection device. Figure 6 is a schematic diagram of a head-up display device 500 .

[0123] The image projection device is a device for projecting an image by optical scanning, and is, for example, a head-up display device.

[0124] For example, Figure 5As shown, the head-up display device 500 is arranged near the windshield (e.g., windshield 401) of the automobile 400. The projection light emitted from the head-up display device 500 is reflected by the windshield 401 and propagates to the observer (i.e., the user, the driver 402). Therefore, the driver 402 can see the image projected by the head-up display device 500 as a virtual image, etc. For example, a stacking mirror may be provided on the inner surface of the windshield so that the user can visually recognize the virtual image using the projection light emitted by the stacking mirror.

[0125] like Figure 6 As shown, in the head-up display device 500, red, green and blue laser sources 501R, 501G, 501B emit laser light. The emitted laser light passes through an incident optical system including collimating lenses 502, 503, 504, two dichroic mirrors 505, 506 and a light quantity adjustment unit 507 provided for each laser source, and is deflected by a movable device 13 including a reflection surface 14. Then, the deflected laser light passes through a projection optical system including a free-form surface mirror 509, an intermediate screen 510 and a projection mirror 511, thereby being projected onto a screen. In the head-up display device 500, the laser sources 501R, 501G, 501B, the collimating lenses 502, 503, 504 and the dichroic mirrors 505, 506 are integrated into a light source unit 530 by an optical housing.

[0126] The head-up display device 500 projects the intermediate image displayed on the intermediate screen 510 onto the windshield 401 of the car 400 so that the driver 402 can visually recognize the intermediate image as a virtual image.

[0127] The lasers of corresponding colors emitted from the laser sources 501R, 501G, and 501B are respectively converted into substantially parallel light by the collimating lenses 502, 503, and 504, and are combined by two dichroic mirrors 505 and 506 used as combining units. The light amount of the combined laser light is adjusted by the light amount adjusting unit 507, and then the combined laser light is moved two-dimensionally by the movable device 13 including the reflecting surface 14 to generate the projection light L for scanning. The free-form surface mirror 509 reflects the projection light L to correct the distortion of the projection light L, and the corrected projection light L is gathered on the intermediate screen 510, thereby showing the intermediate image. The intermediate screen 510 is composed of a microlens array, and the microlenses in the microlens array are arranged two-dimensionally, and the projection light L incident on the intermediate screen 510 is magnified in units of microlenses.

[0128] The movable device 13 reciprocates the reflecting surface 14 in two axial directions, thereby two-dimensionally scanning the projection light L incident on the reflecting surface 14. The driving control of the movable device 13 is performed in synchronization with the emission timing of the laser light sources 501R, 501G, 501B.

[0129] In the above, the head-up display device 500 is described as an example of the image projection device, but the image projection device may be a device that projects an image by optically scanning using the movable device 13 having the reflective surface 14. For example, the image projection device may be implemented in a similar manner as a projector placed on a structure such as a table to project an image onto a display screen, or as a head-mounted display device mounted on a mounting member attached to a portion of the observer's head, etc. to project an image onto a transparent reflective screen of the mounting member, or onto the retina of an eye as a screen, and so on.

[0130] The image projection device can be installed not only on vehicles and mounting structures, but also on mobile objects such as airplanes, ships, movable robots, etc., and can also be installed on immovable objects such as working robots, such as manipulators for manipulating targets without leaving their original positions.

[0131] It should be noted that the head-up display device 500 is an example of a “head-up display.” The automobile 400 is an example of a “vehicle.”

[0132] <Optical Writing Device>

[0133] The following will refer to Figure 7 and Figure 8 The optical writing device including the movable device 13 of this embodiment is described in detail.

[0134] Figure 7 is a schematic diagram of an imaging device provided with an optical writing device 600. Figure 8 is a schematic diagram of an optical writing device.

[0135] like Figure 7 As shown, the optical writing device 600 is a component of the imaging device. The imaging device can be, for example, a laser printer 650 having a printer function using laser. In the imaging device, the optical writing device 600 uses one or more laser beams to scan the photosensitive drum as the scanning surface 15 to optically write an image on the photosensitive drum.

[0136] like Figure 8As shown, in the optical writing device 600, the laser light emitted from the light source device 12 (e.g., a laser device) passes through an imaging optical system 601 (e.g., a collimating lens, etc.), and then the laser light is deflected in a single axial direction or two axial directions by a movable device 13 including a reflective surface 14. Subsequently, the laser light deflected by the movable device 13 passes through a scanning optical system 602 including a first lens 602a, a second lens 602b, and a reflective mirror unit 602c, thereby being emitted onto a scanning surface 15 (e.g., a photosensitive drum and photosensitive paper) for optical writing. The scanning optical system 602 forms a light beam in a spot shape on the scanning surface 15. The light source device 12 and the movable device 13 including the reflective surface 14 are driven under the control of the control device 11.

[0137] In this way, the optical writing device 600 can be used as a component of an imaging device having a laser printer function. The optical writing device 600 can also be used as a component of an imaging device such as a laser marking device that deflects laser light not only in a single axial direction but also in two axial directions by controlling a scanning optical system to scan and heat a thermal medium with laser light, thereby printing on the thermal medium.

[0138] Compared with the rotating polygonal mirror, the movable device 13 with the reflective surface 14 for the optical writing device consumes less driving power, so it is helpful to save the power consumption of the optical writing device. In addition, compared with the rotating polygonal mirror, the wind noise caused by the vibration of the movable device 13 is smaller, so the movable device 13 is helpful to improve the quietness of the optical writing device. In addition, compared with the rotating polygonal mirror, the optical writing device occupies a much smaller space, and the heat generated by the movable device 13 is negligible, so it is easy to reduce the size of the optical writing device. Therefore, the movable device 13 with the reflective surface 14 for the optical writing device is helpful to reduce the size of the imaging device.

[0139] <Object Recognition Device>

[0140] The following will refer to Fig. 9 and Fig.10 The object recognition device including the mobile device of this embodiment is described in detail.

[0141] Fig. 9 is a schematic diagram of a car equipped with a LiDAR (Laser Imaging Detection and Ranging) device. The LiDAR device is an example of an object recognition device. Fig.10 is a schematic diagram of a LiDAR device.

[0142] The object recognition device is a device for recognizing an object in a target direction, such as a LiDAR device.

[0143] like Fig. 9As shown, a LiDAR device 700 is installed on, for example, a car 701 to recognize a target object 702 by optically scanning in a target direction and receiving light reflected by the target object 702 existing in the target direction.

[0144] like Fig.10 As shown, the laser emitted from the light source device 12 passes through an incident optical system including a collimating lens 703 and a plane mirror 704. The collimating lens 703 is used to convert the divergent light into a substantially parallel light. Then, the laser is scanned in a single axial direction or two axial directions using a movable device 13 including a reflective surface 14. Then, the laser passes through a projection laser 705 (i.e., a projection optical system, etc.), and the target object 702 in front of the LiDAR device 700 is irradiated with the laser passing through the projection laser 705. The control device 11 controls and drives the light source device 12 and the movable device 13. The reflected light reflected by the target object 702 is optically detected by an optical detector 709. Specifically, the reflected light passes through a collimating lens 706 (i.e., an incident light detection and receiving optical system, etc.), thereby being received by an image acquisition device 707, and the image acquisition device 707 outputs a detection signal to a signal processing circuit 708. The signal processing circuit 708 performs predetermined processing (eg, binarization, noise processing, etc.) on the received detection signal, and outputs the result to the distance measurement circuit 710 .

[0145] The distance measurement circuit 710 identifies the presence of the target object 702 based on the time difference between the time point when the light source device 12 emits the laser and the time point when the optical detector 709 receives the laser or based on the phase difference in each pixel of the image received by the image acquisition device 707, and also calculates distance information about the distance to the target object 702.

[0146] Compared with a polygonal mirror, the movable device 13 including the reflecting surface 14 is less susceptible to damage and is small in size. Therefore, the movable device 13 including the reflecting surface 14 can provide a compact radar device with high durability. Such a LiDAR device is installed on a vehicle, an airplane, a ship, a robot, etc., for example, and the LiDAR device can identify the presence of an obstacle and the distance to the obstacle by optically scanning a predetermined range.

[0147] The object recognition device is described above by taking the LiDAR device 700 as an example, and is therefore not limited to the embodiments described above. The object recognition device may be a device that recognizes the target object 702 by causing the control device 11 to control the movable device 13 having the reflective surface 14 and causing the optical detector to receive reflected light for optical scanning.

[0148] For example, the object recognition device can also be similarly used in the following devices: (i) a biometric authentication device that calculates object information (such as shape) based on distance information obtained by optically scanning a hand or face and identifies a target object with reference to a record, (ii) a security sensor that identifies an intruding object by performing an optical scan within a target range, (iii) a three-dimensional scanner that calculates and identifies object information (such as shape) based on distance information obtained by performing an optical scan and outputs the object information as three-dimensional data, and the like.

[0149] <Laser headlight>

[0150] The following will refer to Fig.11 A laser headlight 50 for a car including the movable device of this embodiment is described. Fig.11 2 is a schematic diagram for explaining an example of the structure of the laser headlight 50 .

[0151] The laser headlight 50 includes a control device 11 , a light source device 12 b , a movable device 13 including a reflecting surface 14 , a reflecting mirror 51 , and a transparent plate 52 .

[0152] The light source device 12b is a light source that emits blue laser light. The light emitted from the light source device 12b is incident on the movable device 13 and is reflected by the reflection surface 14. The movable device 13 moves the reflection surface in the XY direction according to the signal given by the control device 11, and causes the blue laser light emitted from the light source device 12b to perform two-dimensional scanning in the XY direction.

[0153] The scanning light from the movable device 13 is reflected by the reflector 51 and is incident on the transparent plate 52. The front surface or the rear surface of the transparent plate 52 is coated with a yellow fluorescent substance. When the blue laser light reflected by the reflector 51 passes through the yellow fluorescent substance coating on the transparent plate 52, the blue laser light becomes white light within the legal range specified as the headlight color. As a result, the area in front of the car is illuminated by the white light passing through the transparent plate 52.

[0154] The scanning light from the movable device 13 is scattered when it passes through the fluorescent substance of the transparent plate 52. This reduces the glare to the lighting target in front of the car.

[0155] In the case where the movable device 13 is used for the headlight of an automobile, the colors of the light source device 12b and the fluorescent substance are not limited to blue and yellow, respectively. For example, the light source device 12 may be configured to emit near-ultraviolet light, and the transparent plate 52 may be covered with a uniform mixture of fluorescent substances of the three primary colors of light (i.e., blue, green, and red). Even in this case, the light passing through the transparent plate 52 can be converted into white light, and the area in front of the automobile can be illuminated by the white light.

[0156] <Head-mounted display>

[0157] The following will refer to Fig.12 and Fig.13 A head mounted display 60 including a mobile device of this embodiment is described. Here, the head mounted display 60 is a head mounted display that can be worn on a person's head, and can be configured in a shape similar to glasses, for example. The head mounted display is hereinafter referred to as HMD for short.

[0158] Fig.12 is a schematic diagram showing an example of the HMD 60. Fig.12 In the embodiment, the HMD 60 is composed of a pair of front parts 60a and a pair of temple parts 60b which are substantially symmetrically arranged on the left and right sides. The front part 60a may be composed of, for example, a light guide plate 61. The temple parts 60b may be provided with an optical system, a control device, and the like.

[0159] Fig.13 is a schematic diagram of an example of a partial configuration of the HMD 60. Fig.13 The configuration for the left eye is shown, but the HMD 60 also has the same configuration for the right eye.

[0160] The HMD 60 includes a control device 11 , a light source unit 530 , a light amount adjustment unit 507 , a movable device 13 including a reflection surface 14 , a light guide plate 61 , and a half mirror 62 .

[0161] As described above, the light source unit 530 is obtained by integrating the laser light sources 501R, 501G, 501B, the collimating lenses 502, 503, 504, and the dichroic mirrors 505, 506 using an optical housing. In the light source unit 530, the three colors of laser light emitted from the laser light sources 501R, 501G, 501B are combined by the dichroic mirrors 505, 506 as a combining unit. The light source unit 530 emits the combined parallel light.

[0162] The light amount of the light from the light source unit 530 is adjusted by the light amount adjustment unit 507, and then the light is incident on the movable device 13. The movable device 13 moves the reflection surface 14 in the XY direction according to the signal given by the control device 11 so that the light emitted from the light source unit 530 performs two-dimensional scanning. The movable device 13 is driven and controlled in synchronization with the light emission timing of the laser light sources 501R, 501G, 501B to generate scanning light that forms a color image.

[0163] The scanning light emitted 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 by reflecting the scanning light on the inner wall surface. The light guide plate 61 is made of a material such as resin transparent to the wavelength of the scanning light.

[0164] The half mirror 62 reflects the light from the light guide plate 61 to the back of the HMD 60 to emit the light in the direction of the eyes of the wearer 63 of the HMD 60. The half mirror 62 has, for example, a free-form surface shape. An image of the scanned light is formed on the retina of the wearer 63 by reflection at the half mirror 62. Alternatively, an image is formed on the retina of the wearer 63 by reflection at the half mirror 62 and the lens effect of the lens in the eyeball. By reflection at the half mirror 62, spatial distortion of the image is corrected. The wearer 63 can see an image formed by light scanning in the XY direction.

[0165] The wearer 63 can see an image formed by light from the outside and an image formed by the scanning light in a superimposed manner using the half mirror 62. Alternatively, a reflective mirror may be provided instead of the half mirror 62 to block light from the outside, so that the HMD 60 is configured so that the wearer can see only the image formed by the scanning light.

[0166] <Package>

[0167] The following will refer to Fig.14 The packaging of the mobile device of this embodiment is described.

[0168] Fig.14 is a schematic diagram of a packaged movable device.

[0169] like Fig.14 As shown, the movable device 13 is attached to an attachment member 802 provided in a packaging member 801, and is packaged by a transparent member 803 that seals and covers a portion of the packaging member 801. In addition, the package is sealed using an inert gas such as nitrogen. This reduces the degradation of the movable device 13 due to oxidation and improves durability against environmental changes (such as temperature changes).

[0170] The details of the movable device of this embodiment used in the above-mentioned optical deflection system, optical scanning system, image projection device, optical writing device, object recognition device, laser headlight and head-mounted display will be described below with reference to the accompanying drawings. In the accompanying drawings, the same constituent elements may be denoted by the same reference numerals, and the related repeated description may be omitted.

[0171] In the description of the embodiment, the optical scanning performed with the first axis as the rotation center is referred to as the sub-scan, and the optical scanning performed with the second axis as the rotation center is referred to as the main scan. In the embodiment, "rotation", "swing" and "movement" are assumed to be synonymous. In addition, among the directions indicated by the arrows, the X direction is a direction parallel to the first axis, the Y direction is a direction parallel to the second axis, and the Z direction is a direction perpendicular to the XY plane. The Z direction is an example of a "superimposed direction".

[0172] <First Embodiment>

[0173] First, a uniaxial light deflector (ie, movable device) will be described. Fig.15 FIG. 9 is a plan view of a two-end support type optical deflector 900 capable of swinging around a first axis. Fig.15 As shown, for example, the light deflector 900 includes a circular reflector unit 901, a mirror reflection surface 902 formed on the +Z surface of the substrate of the reflector unit 901, etc. For example, the reflector unit 901 is made of a silicon layer. The reflector unit 901 can be made of an oxide material, an inorganic material or an organic material, for example. The reflector unit 901 can be made of a plurality of materials or a multilayer composed of the same material, for example. The mirror reflection surface 902 is made of a metal film or a multilayer film containing aluminum, gold, silver, etc., for example. A rib structure for strengthening the reflector unit can be formed on the -Z surface of the substrate of the reflector unit 901. The rib is made of a silicon support layer and a silicon oxide layer, for example, and reduces the distortion of the reflector unit 901 and the mirror reflection surface 902 caused by movement.

[0174] The movable unit 903 including the reflector unit 901 and the mirror reflecting surface 902 is rotatably supported by the supporting parts 904a and 904b constituting a pair of actuators. Specifically, one end (first end) of each of the supporting parts 904a and 904b is connected to the movable unit 903 via the movable unit connecting unit 905. The other end (second end) of each of the supporting parts 904a and 904b opposite to the end is connected to the fixing unit 908.

[0175] exist Fig.15 , the fixed unit 908 is formed in a frame shape, but the fixed unit 908 does not necessarily have to be formed in a frame shape. The fixed unit 908 may have an actuator for applying deformation to the movable unit 903, or may be connected to an actuator for moving the fixed unit 908. The support portions 904a, 904b are provided with a plurality of beam units 915 extending in the Y direction. Adjacent beam units 915 are connected by connection units 916 alternately arranged on the +Y side and the -Y side to form a zigzag structure.

[0176] Specifically, the support portions 904a, 904b have a zigzag structure (bellows structure) in which the beam unit 915 extending in the Y direction is connected by a connecting unit 916 so that the beam unit 915 is folded back. Piezoelectric drive unit groups 925A and piezoelectric drive unit groups 925B are alternately provided on the +Z surface of each beam unit 915. The fixed unit 908 is provided with an electrical contact electrode terminal 909. An electric wire (not shown) is provided to connect the electrical contact electrode terminal 909 to the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B. A voltage signal is input to the electrical contact electrode terminal 909 to apply the voltage signal to the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B via the electric wire, so that the movable unit 903 including the reflector unit 901 can be moved around the first axis (i.e., Figure 1 X-axis) rotation.

[0177] In the light deflector 900 , the lengths of the beam units 915 in the Y direction are formed to be substantially the same as each other, and the +Y end and the −Y end of the beam unit 915 are aligned in the X-axis direction.

[0178] Fig.16 It is along Fig.15 15A-15B of the cross-sectional view. The beam unit 915 of the support portion 904a having a zigzag structure and the substrate of the movable unit connection unit 905 are made of an elastic silicon layer 930. In addition, the beam unit 915 and the substrate of the movable unit connection unit 905 have rigidity and can be made of any material that can be processed by a semiconductor process, such as an inorganic material, an organic material, a metallic glass, etc. Alternatively, the beam unit 915 and the substrate of the movable unit connection unit 905 may have a multilayer structure including a plurality of layers made of a plurality of materials.

[0179] The piezoelectric drive unit constituting the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B is formed by sequentially stacking a lower electrode 931, a piezoelectric layer 932 and an upper electrode 933 on the +Z surface of the elastic silicon layer 930. The lower electrode 931 and the upper electrode 933 are made of, for example, gold (Au) or platinum (Pt). The piezoelectric layer 932 is made of, for example, PZT (lead zirconate titanate) (i.e., a piezoelectric material). However, the piezoelectric layer 932 may also be made of other piezoelectric materials and is not limited to any specific type. The piezoelectric drive unit may have a structure including a plurality of stacked piezoelectric layers and including an intermediate electrode. The piezoelectric drive unit is a piezoelectric actuator electrically connected to an external control device and is configured to be driven by applying a voltage. The piezoelectric drive unit in the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B may be covered with an insulating film (not shown) made of silicon oxide, etc., and an electric wire may be formed on the +Z surface of the insulating film.

[0180] The movable unit connection unit 905 includes a silicon layer 930, an interlayer film 941 stacked on the -Z surface of the silicon layer 930, and a support layer 942. The interlayer film 941 is formed of an insulating film (e.g., silicon oxide). The support layer 942 is made of single crystal silicon, but the support layer 942 is not limited to silicon as long as the support layer 942 can support the silicon layer 390 and keep the silicon layer 930 fixed in place. An insulating film and a wire (not shown) may be formed on the +Z surface of the movable unit 903, the connection unit 916, and the movable unit connection unit 905.

[0181] In having Fig.15 In the uniaxial optical deflector of the structure shown, voltage is applied to the piezoelectric drive units in the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B, so that the movable unit 903 can rotate around the first axis.

[0182] In order to improve Fig.15 The deflection angle of the reflector in the uniaxial optical deflector of the structure shown can be conceived by increasing the length of the beam unit 915 used as a vibration beam constituting the meander structure. However, when the length of the beam unit 915 used as a vibration beam is increased, the natural resonance frequency of the entire actuator is reduced. Therefore, the mechanical strength is reduced and it is easy to shake.

[0183] Therefore, there is a need for an optical deflector that can mitigate the reduction in natural resonance frequency and achieve a large scanning angle.

[0184] Next, the biaxial light deflector will be described. Fig.17 950 is a plan view of a light deflector 950 that is a double-end support type and can swing around a first axis and a second axis. In a dual-axis light deflector, the light deflector 950 is generally driven to swing around one axis under resonant vibration at a mechanical resonance frequency, and is generally driven to swing around the other axis under non-resonant vibration.

[0185] In such Fig.17 In the light deflector 950 shown, a movable unit 953 including a reflector unit 901 and a mirror reflecting surface 902 is supported by support portions 904a, 904b constituting a pair of actuators. One end of the movable unit 953 is connected to the reflector unit 901, and the other end of the movable unit 953 is connected to movable unit beams 957a, 957b. The light deflector 950 includes torsion beams 956a, 956b supporting the reflector unit 901, so that the reflector unit 901 is between the torsion beams 956a, 956b in the second axial direction. Both ends of the movable unit beams 957a, 957b are connected to the inner side of the movable unit 953 in a frame shape, so that the torsion beams 956a, 956b are between the movable unit beams 957a, 957b.

[0186] For example, in the case where the torsional resonance frequency of the torsional beams 956a, 956b is set to about 20kHz, a driving signal near the resonance frequency is input to the piezoelectric driving unit provided on the +Z surface of the movable unit beams 957a, 957b connected to the torsional beams 956a, 956b. As a result, the movable unit beams 957a, 957b vibrate to induce a torsion of mechanical resonance in the torsional beams 956a, 956b, so that the movable unit 953 can be moved around the second axis (i.e., Figure 1 In addition, by combining this vibration around the second axis with the swing of the movable unit 953 around the first axis using the support parts 904a, 904b of the zigzag structure, Lissajous scanning and raster scanning can be performed.

[0187] I also hope that Fig.17 The dual-axis light deflector 950 shown is able to mitigate the reduction in natural resonant frequency and achieve large scanning angles.

[0188] (Light Deflector)

[0189] Next, a light deflector 100 (ie, movable device) of the first embodiment will be described. Fig.18 1 is a plan view of the light deflector 100, which is a double-ended support type and can make the movable unit 103 rotate around the first axis (rotation axis) (ie, Fig.18 The light deflector 100 of this embodiment is as follows Fig.18 The single-axis light deflector shown.

[0190] like Fig.18 As shown, for example, the light deflector 100 includes a circular reflector unit 101, a mirror reflection surface 102 formed on the +Z surface of the substrate of the reflector unit 101, etc. For example, the reflector unit 101 is made of a silicon layer. The reflector unit 101 can be made of an oxide material, an inorganic material or an organic material, for example. The reflector unit 101 can be made of multiple materials or multiple layers composed of the same material, for example. The mirror reflection surface 102 is made of a metal film or a multilayer film containing aluminum, gold, silver, etc., for example. A rib structure for strengthening the reflector unit can be formed on the -Z surface of the substrate of the reflector unit 101. The rib is made of a silicon support layer and a silicon oxide layer, for example, and reduces the distortion of the reflector unit 101 and the mirror reflection surface 102 caused by movement.

[0191] The movable unit 103, which is substantially circular and includes a reflector unit 101 and a mirror reflecting surface 102, is rotatably supported by support parts 104a and 104b constituting a pair of actuators. Specifically, one end (first end) of each of the support parts 104a and 104b is connected to the movable unit 103 via a movable unit connecting unit 105. The other end (second end) of each of the support parts 104a and 104b opposite to the end is connected to a fixing unit 108.

[0192] exist Fig.15 In the embodiment, the fixed unit 108 is formed into a frame shape, but the fixed unit 108 does not necessarily have to be formed into a frame shape. The support parts 104a, 104b are provided with a plurality of beam units 115. Adjacent beam units 115 are connected by connecting units 116 alternately arranged on the +Y side and the -Y side to form a zigzag structure. It should be noted that the reflector unit 101 and the movable unit 103 can be formed into an ellipse or a polygon.

[0193] The beam units 115 in the support portions 104 a , 104 b are formed in an arc shape whose center coincides with the center of the substantially circular movable unit 103 , and these support portions are formed to have the same width in the Y direction.

[0194] Specifically, if Fig.18 As shown, the line L1 connecting the +Y ends of the plurality of beam units 115 is formed to be parallel to the first axis, and the line L2 connecting the -Y ends of the plurality of beam units 115 is formed to be parallel to the first axis. In addition, the line L3 connecting the +Y ends of the connection units 116 connecting the beam units 115 together is formed to be parallel to the first axis, and the line L4 connecting the -Y ends of the connection units 116 connecting the beam units 115 together is formed to be parallel to the first axis.

[0195] In the supporting parts 104a and 104b, the closer the beam unit 115 among the plurality of beam units 115 is to the movable unit 103, the smaller the curvature radius of the beam unit 115. For example, in the supporting part 104a, the curvature radius R12 of the beam unit 115 closest to the fixed unit 108 and farthest from the movable unit 103 is greater than the curvature radius R11 of the beam unit 115 closest to the movable unit 103. Since the widths of the beam units 115 in the Y direction are the same, the length of the beam unit 115 having a small curvature radius R11 and closest to the movable unit 103 is greater than the length of the beam unit 115 having a large curvature radius R12 and closest to the fixed unit 108.

[0196] Longer beam elements 115 are easier to move, while shorter beam elements 115 have higher stiffness and are less likely to move. In this disclosure, the term "stiffness" is used. The term "stiffness" refers to the degree of resistance to movement caused by a specific force applied to a beam element. In other words, when a certain force is applied, a beam element with greater stiffness is less likely to move than a beam element with less stiffness.

[0197] Therefore, in the light deflector 100 of this embodiment, the farther the beam unit 115 among the plurality of beam units 115 of the supporting parts 104a, 104b is from the movable unit 103, the shorter the beam unit 115 is, and thus the greater its rigidity is. Specifically, if the supporting parts 104a, 104b are divided into two parts at a predetermined or given position, the beam unit 115 closer to the movable unit 103 is longer than the beam unit 115 closer to the fixed unit 108, and the rigidity of the beam unit 115 closer to the fixed unit 108 is higher than that of the beam unit 115 closer to the movable unit 103.

[0198] exist Fig.18 In the embodiment, the movable unit 103 is supported by two supporting portions 104a and 104b provided on the +X side and the -X side of the movable unit 103, but as will be described later with reference to Fig.24 As mentioned above, the movable unit 103 may also be supported by a single support portion to rotate around the first axis.

[0199] In the above manner, the support portions 104a, 104b constitute a zigzag structure in which the arc-shaped beam unit 115 is connected by the connecting unit 116, so that the beam unit 115 is folded back. Piezoelectric drive unit groups 125A and piezoelectric drive unit groups 125B are alternately provided on the +Z surface of each beam unit 115. The fixed unit 108 is provided with an electrical contact electrode terminal 109. An electric wire (not shown) is provided to connect the electrical contact electrode terminal 109 with the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B. A voltage signal is input to the electrical contact electrode terminal 109 to apply the voltage signal to the piezoelectric drive unit in the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B via the electric wire, so that the movable unit 103 including the mirror unit 101 can rotate around the first axis.

[0200] Fig.19 It is along Fig.18 18A-18B. The substrate of the beam unit 115 having the support portion 104a of the zigzag structure is made of an elastic silicon layer 130. In addition, the substrate of the beam unit 115 has rigidity and can be made of any material that can be processed by a semiconductor process, such as an inorganic material, an organic material, a metallic glass, etc. Alternatively, the substrate of the beam unit 115 may have a multilayer structure including a plurality of layers made of a plurality of materials.

[0201] The piezoelectric drive unit constituting the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B is formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132 and an upper electrode 133 on the +Z surface of the elastic silicon layer 133. The lower electrode 131 and the upper electrode 133 are made of, for example, gold (Au) or platinum (Pt). The piezoelectric layer 132 is made of, for example, PZT (lead zirconate titanate) (i.e., a piezoelectric material). However, the piezoelectric layer 132 may also be made of other piezoelectric materials and is not limited to any specific type. The piezoelectric drive unit may have a structure including a plurality of stacked piezoelectric layers and including an intermediate electrode. The piezoelectric drive unit is a piezoelectric actuator electrically connected to an external control device and is configured to be driven by applying a voltage. The piezoelectric drive unit in the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B may be covered with an insulating film (not shown) made of silicon oxide, etc., and an electric wire may be formed on the +Z surface of the insulating film.

[0202] The movable unit connection unit 105 includes a silicon layer 130, an interlayer film stacked on the -Z surface of the silicon layer 130, and a silicon support layer in sequence. The interlayer film is formed of an insulating film (e.g., silicon oxide). The support layer is made of single crystal silicon, but the support layer is not limited to silicon as long as the support layer can support the silicon layer 130 and keep the silicon layer 130 fixed in place. An insulating film and a wire (not shown) may be formed on the +Z surface of the movable unit 103, the connection unit 116, and the movable unit connection unit 105.

[0203] In having Fig.18 In the uniaxial optical deflector of the structure shown, voltage is applied to the piezoelectric drive units in the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B, so that the movable unit 103 can rotate around the first axis.

[0204] In this embodiment, the beam unit 115 closer to the fixed unit 108 is shorter than the beam unit 115 closer to the movable unit 103 and has a higher rigidity. Therefore, the entire length of the support parts 104a, 104b constituting the actuator is increased, and the rigidity of the beam unit 115 closer to the fixed unit 108 is higher. Therefore, a large scanning angle can be obtained while improving the mechanical strength against resonance. It should be noted that, compared with the case where the rigidity of the beam unit 115 closer to the movable unit 103 is higher than the rigidity of the beam unit 115 closer to the fixed unit 108, the mechanical strength against resonance is higher when the rigidity of the beam unit 115 closer to the fixed unit 108 is higher than the rigidity of the beam unit 115 closer to the movable unit 103.

[0205] Fig. 20 It shows that Fig.15 The light deflector shown in FIG. Fig.18The relationship between the resonance frequency of the first mode and the deflection angle of the reflector (i.e., the swing angle of the movable unit 103) in the light deflector of this embodiment is shown. The resonance frequency of the first mode is the lowest resonance frequency among the resonance frequencies. The deflection angle of the reflector corresponds to the scanning angle of the reflector. Fig. 20 As shown, in Fig.18 In the optical deflector of this embodiment shown in FIG. 1 , the resonance frequency of the first mode and the deflection angle of the reflector are both higher than those of the embodiment shown in FIG. Fig.15 The corresponding values ​​in the light deflector are shown.

[0206] like Fig.18 As shown, in the optical deflector 100 of this embodiment, the line L1 connecting the +Y ends of the plurality of beam units 115 is formed to be parallel to the first axis, and the line L2 connecting the -Y ends of the plurality of beam units 115 is formed to be parallel to the first axis. In this way, the width between the first axis and the end of the beam unit 115 that contributes to the rotational torque is constant, so that the rotational force can be efficiently transmitted to the movable unit 103. Specifically, unless the width between the first axis and the end of the beam unit 115 is constant, the vibrations that contribute to the deflection angle in each beam unit 115 become out of phase, and when the deflection angle increases, these out-of-phase vibrations cause nonlinear vibrations, thereby causing rotational instability. Therefore, in order to stably rotate the movable unit 103 around the first axis, the width between the first axis and the end of the beam unit 115 is preferably constant.

[0207] Fig.21 is a plan view of a light deflector 100A according to a modification of the light deflector 100 of the first embodiment. Fig.21 The light deflector 100A includes a separate fixing unit 108 .

[0208] Fig. 22 FIG. 1 is a plan view of a light deflector 100B which is a variation of the light deflector 100 according to the first embodiment. Fig. 22 As shown, the support parts 104a, 104b may be formed so that the width between the ends in the Y direction of the beam unit 115 closer to the movable unit 103 is larger, and the width between the ends in the Y direction of the beam unit 115 closer to the fixed unit 108 is smaller. In this case, in the support parts 104a, 104b, the length of the beam unit 115 closer to the movable unit 103 may be increased more than the length of the beam unit 115 closer to the fixed unit 108.

[0209] In this case, if Fig. 22As shown, the shape of the support portion 104a is preferably such that the intersection point between the extension line L11 connecting the end of the +Y side connection unit 116 and the extension line L12 connecting the end of the -Y side connection unit 116 is located on the first axis. Although not shown, the support portion 104b is preferably fan-shaped, in which the intersection point between the extension line connecting the end of the +Y side connection unit 116 and the extension line connecting the end of the -Y side connection unit 116 is located on the first axis. In the case where the support portions 104a, 104b are formed so that the intersection point between the extension line connecting the end of the +Y side connection unit 116 and the extension line connecting the end of the -Y side connection unit 116 is located on the first axis, the movable unit 103 can swing around the first axis in a stable manner.

[0210] Fig.23 FIG. 1 is a plan view of a light deflector 100C which is a variation of the light deflector 100 according to the first embodiment. Fig.23 As shown, the light deflector 100C may be formed such that a gap between the fixing unit 108 and the supporting parts 104a, 104b is reduced.

[0211] Fig.24 FIG. 1 is a plan view of a light deflector 100D which is a variation of the light deflector 100 according to the first embodiment. Fig.24 As shown, the light deflector 100D may include a single support portion 104 a disposed between the fixed unit 108 and the movable unit 103 for supporting the movable unit 103 .

[0212] Fig.25 FIG. 1 is a plan view of a light deflector 100E which is a variation of the light deflector 100 according to the first embodiment. Fig.25 As shown, the light deflector 100E may include three supporting portions, ie, supporting portions 104 c , 104 d , and 104 e , disposed between the fixed unit 108 and the movable unit 103 for supporting the movable unit 103 . Fig.26 FIG. 1 is a plan view of a light deflector 100F which is a variation of the light deflector 100 according to the first embodiment. Fig.26 As shown, the optical deflector 100F may include four supporting parts, ie, supporting parts 104f, 104g, 104h, and 104i, disposed between the fixed unit 108 and the movable unit 103 for supporting the movable unit 103. Fig.25 and Fig.26 In the light deflectors 100E and 100F shown, the deflection direction of light is not limited to a single axis, and light can be deflected in multiple axial directions.

[0213] Fig. 27 FIG. 1 is a plan view of a light deflector 150 which is a variation of the light deflector 100 according to the first embodiment. Fig. 27As shown, the light deflector 150 is a dual-axis light deflector.

[0214] In such Fig. 27 In the light deflector 150 shown, a movable unit 153 including a reflector unit 101 and a mirror reflecting surface 102 is supported by support portions 104a, 104b constituting a pair of actuators. One end of the movable unit 153 is connected to the reflector unit 101, and the other end of the movable unit 153 is connected to movable unit beams 157a, 157b. The light deflector 150 includes torsion beams 156a, 156b supporting the reflector unit 101, so that the reflector unit 101 is between the torsion beams 156a, 156b in the second axial direction. Both ends of the movable unit beams 157a, 157b are connected to the inner side of the movable unit 153 in a frame shape.

[0215] In this embodiment, the movable unit 153 is supported in such a manner that the movable unit 153 can be resonantly driven by the movable unit beams 157a, 157b. For example, when the torsional resonance frequency of the torsional beams 156a, 156b is set to about 20kHz, a drive signal near the resonance frequency is input to a piezoelectric drive unit disposed on the +Z surface of the movable unit beams 157a, 157b connected to the torsional beams 156a, 156b. As a result, the movable unit beams 157a, 157b vibrate to cause a torsion of mechanical resonance in the torsional beams 156a, 156b, so that the movable unit beams 157a, 157b can rotate the reflector unit 101 around the second axis.

[0216] In this biaxial optical deflector, since the resonance frequency of the vibration generated by the supporting portions 104a and 104b is high and the deflection angle is large, vibration mixing with the vibration generated by the movable unit beams 157a and 157b can be reduced.

[0217] In the above description, the piezoelectric layer 132 is provided on the support parts 104a, 104b constituting the actuator to realize piezoelectric driving. Alternatively, in this embodiment, the support parts 104a, 104b may be deformed under the action of an electromagnetic field to realize electromagnetic driving, or comb-shaped electrodes may be formed in the support parts 104a, 104b. A coil or a magnet array may be formed on the support parts 104a, 104b constituting the beam. The support parts 104a, 104b may be driven by resonant driving or non-resonant driving.

[0218] <Variation of the First Embodiment>

[0219] A light deflector (ie, movable device) according to a modified embodiment of the first embodiment will be described below. In the modified embodiment of the first embodiment, in the beam unit of the support portion, not only the length but also the thickness and the width are changed.

[0220] Fig.28 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100 of the first embodiment. Fig.28 As shown, the planar shape of the light deflector of this embodiment is similar to Fig.18 The planar shapes of the light deflectors shown are the same. Each of the support portions 204a, 204b provided on both sides of the movable unit 103 in the X direction includes a beam unit 215a closer to the movable unit 103 and a beam unit 215b closer to the fixed unit 108. The beam unit 215b is thicker than the beam unit 215a.

[0221] Fig.29 It is along Fig.28 The cross-sectional view is taken along the dotted line 28A-28B. Fig.29 As shown, the two beam units 215b closer to the fixed unit 108 are formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 on the +Z surface of the silicon layer 130. A silicon oxide layer 231 and a silicon layer 232 are sequentially stacked on the -Z surface of the silicon layer 130, and the thickness of the stacked silicon layer 232 is, for example, 30 microns to 40 microns. The two beam units 215a closer to the movable unit 103 are formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 on the +Z surface of the silicon layer 130, but the beam unit 215a does not include the silicon oxide layer 231 and the silicon layer 232 on the -Z surface. Therefore, the beam unit 215b is shorter and thicker than the beam unit 215a. Compared with the first embodiment, the beam unit 215b has a higher rigidity than the beam unit 215a. Although Fig.28 A structure having two layers (ie, the silicon oxide layer 231 and the silicon layer 232 ) stacked in sequence is shown, but a single layer may also be formed on the −Z surface of the silicon layer 130 .

[0222] Fig.30 It is along Fig.28 The cross-sectional view taken along the dotted line 28C-28D is shown. Fig.30As shown, the connection unit 216b connecting the two beam units 215b is formed by sequentially stacking a silicon oxide layer 231, a silicon layer 232, a silicon oxide layer 233 and a silicon support layer 234 on the -Z surface of the silicon layer 130. In contrast, in the connection unit 216a connecting the two beam units 215a, no material is provided on the -Z surface of the silicon layer 130. In this way, on the side of the fixed unit 108, a silicon support layer 234 and the like are formed on the rear surface of the connection unit connecting the beam units constituting the zigzag structure, and it is known that this is effective in reducing unnecessary vibrations of the natural mode and improving the deflection efficiency of each beam unit. Therefore, the thickness of the connection unit 216b closer to the fixed unit 108 is greater than the thickness of the connection unit 216a closer to the movable unit 103, thereby further enhancing the effect of the present disclosure.

[0223] Although Fig.30 A structure is shown in which a plurality of layers (i.e., silicon oxide layer 231, silicon layer 232, silicon oxide layer 233, and silicon support layer 234) are sequentially formed on the rear surface of the connection unit, but a single layer may be formed on the rear surface of the connection unit. In this case, when there are many beam units, the thickness of the layer formed on the rear surface of the connection unit may be relatively increased toward the fixed unit 108 and relatively decreased toward the movable unit 103.

[0224] Fig.31 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100 of the first embodiment. Fig.31 As shown, the width of the beam unit 225 in the support parts 214a, 214b supporting the movable unit 103 from both sides of the movable unit 103 in the X direction increases from the movable unit 103 to the fixed unit 108. When the width of the beam unit 225 increases, the rigidity of the beam unit 225 increases. Specifically, from the movable unit 103 to the fixed unit 108, the length of the beam unit 225 in the support parts 214a, 214b gradually decreases, and the width of the beam unit 225 in the support parts 214a, 214b gradually increases. In other words, in the support parts 214a, 214b, the length of the beam unit 225 closer to the movable unit 103 is greater than the length of the beam unit 225 closer to the fixed unit 108, and the rigidity of the beam unit 225 closer to the fixed unit 108 is higher than the rigidity of the beam unit 225 closer to the movable unit 103. Therefore, the effect of the present disclosure can be further enhanced.

[0225] Fig.32 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100 of the first embodiment. Fig.32As shown, the connection unit 316b connecting the beam unit 115 closer to the fixed unit 108 is formed to be wider than the connection unit 316a connecting the beam unit 115 closer to the movable unit 103. In this way, among the connection units connecting the beam units constituting the zigzag structure, the width of the connection unit 316b closer to the fixed unit 108 is greater than the width of the connection unit 316a closer to the movable unit 103, thereby further enhancing the effect of the present disclosure.

[0226] <Second Embodiment>

[0227] The light deflector 100-2 (i.e., movable device) of the second embodiment will be described below. The configuration of the light deflector 100-2 is similar to that of the light deflector 100 of the first embodiment, except that the beam unit 115 is formed in a shape different from that of the first embodiment, as described below. In the second embodiment, the constituent elements corresponding to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and the corresponding repeated description is appropriately omitted. Fig.33 1 is a plan view of the light deflector 100-2, which is a double-end support type and can make the movable unit 103 rotate around the first axis (rotation axis) (ie, Fig.33 The light deflector 100-2 is as follows Fig.33 The single-axis light deflector shown.

[0228] The beam unit 115 in the support parts 104a, 104b is formed into an arc whose center coincides with the center of the approximately circular movable unit 103, and the length of the beam unit 115 gradually increases from the movable unit 103 to the fixed unit 108. Therefore, in a plan view (i.e., viewed along the Z direction), the shape of the beam unit 115 is an arc that protrudes from the center of the movable unit 103 toward the fixed unit 108. Therefore, the beam unit 115 closer to the fixed unit 108 is longer than the beam unit 115 closer to the movable unit 103, and the beam unit 115 closer to the movable unit 103 is lighter than the beam unit 115 closer to the fixed unit 108. Specifically, if the support parts 104a, 104b are divided into two parts at a predetermined or given position, the beam unit 115 closer to the fixed unit 108 is longer than the beam unit 115 closer to the movable unit 103, and the beam unit 115 closer to the movable unit 103 is lighter than the beam unit 115 closer to the fixed unit 108.

[0229] exist Fig.33 In the embodiment, the movable unit 103 is supported by two supporting portions 104a and 104b provided on the +X side and the -X side of the movable unit 103, but as will be described later with reference to Fig.42 As mentioned above, the movable unit 103 may also be supported by a single support portion to rotate around the first axis.

[0230] In the above manner, the support parts 104a, 104b constitute a zigzag structure in which the arc-shaped beam unit 115 is connected by the connecting unit 116, so that the beam unit 115 is folded back. Piezoelectric drive unit groups 125A and piezoelectric drive unit groups 125B are alternately provided on the +Z surface of each beam unit 115. The fixed unit 108 is provided with an electrical contact electrode terminal 109. An electric wire (not shown) is provided to connect the electrical contact electrode terminal 109 with the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B. A voltage signal is input to the electrical contact electrode terminal 109 to apply the voltage signal to the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B via the electric wire, so that the movable unit 103 including the mirror unit 101 can rotate around the first axis.

[0231] Fig.34 It is along Fig.33 18A-18B. The substrate of the beam unit 115 having the support portion 104a of the zigzag structure is made of an elastic silicon layer 130. In addition, the substrate of the beam unit 115 has rigidity and can be made of any material that can be processed by a semiconductor process, such as an inorganic material, an organic material, a metallic glass, etc. Alternatively, the substrate of the beam unit 115 may have a multilayer structure including a plurality of layers made of a plurality of materials.

[0232] The piezoelectric drive unit constituting the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B is formed by stacking a lower electrode 131, a piezoelectric layer 132 and an upper electrode 133 on the +Z surface of the elastic silicon layer 133. The lower electrode 131 and the upper electrode 133 are made of, for example, gold (Au) or platinum (Pt). The piezoelectric layer 132 is made of, for example, PZT (lead zirconate titanate) (i.e., a piezoelectric material). However, the piezoelectric layer 132 may also be made of other piezoelectric materials and is not limited to any specific type. The piezoelectric drive unit may have a structure including a plurality of stacked piezoelectric layers and including an intermediate electrode. The piezoelectric drive unit is a piezoelectric actuator electrically connected to an external control device and is configured to be driven by applying a voltage. The +Z side of the piezoelectric drive unit in the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B may be covered with an insulating film (not shown) made of silicon oxide, etc., and an electric wire may be formed on the +Z surface of the insulating film.

[0233] The movable unit connection unit 105 includes a silicon layer 130, an interlayer film stacked on the -Z surface of the silicon layer 130, and a silicon support layer. The interlayer film is formed of an insulating film (e.g., silicon oxide). The support layer is made of single crystal silicon, but the support layer is not limited to silicon as long as the support layer can support the silicon layer 130 and keep the silicon layer 130 fixed in place. An insulating film and a wire (not shown) may be formed on the +Z surface of the movable unit 103, the connection unit 116, and the movable unit connection unit 105.

[0234] In having Fig.33 In the uniaxial optical deflector of the structure shown, voltage is applied to the piezoelectric drive units in the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B, so that the movable unit 103 can rotate around the first axis.

[0235] In this embodiment, the beam unit 115 closer to the fixed unit 108 is longer than the beam unit 115 closer to the movable unit 103, and the beam unit 115 closer to the movable unit 103 is lighter than the beam unit 115 closer to the fixed unit 108. Therefore, the entire length of the support parts 104a, 104b constituting the actuator is increased, and the weight of the beam unit 115 closer to the movable unit 103 is lighter. Therefore, a large scanning angle can be obtained while improving the mechanical strength against resonance.

[0236] Fig.35 It shows that Fig.15 The light deflector shown in FIG. Fig.33 The relationship between the resonance frequency of the first mode and the deflection angle of the reflector (i.e., the swing angle of the movable unit 103) in the light deflector of this embodiment is shown. The resonance frequency of the first mode is the lowest resonance frequency among the resonance frequencies. The deflection angle of the reflector corresponds to the scanning angle of the reflector. Fig.35 As shown, in Fig.33 In the optical deflector of this embodiment shown in FIG. 1 , the resonance frequency of the first mode and the deflection angle of the reflector are both higher than those of the embodiment shown in FIG. Fig.15 The corresponding values ​​in the light deflector are shown.

[0237] Fig.36 is a plan view of a light deflector 100 - 2A according to a variation of the light deflector 100 - 2 of the second embodiment. Fig.36 The light deflector 100 - 2A includes a separate fixing unit 108 . Fig.37 FIG. 1 is a plan view of a light deflector 100-2B which is a variation of the light deflector 100-2 according to the first embodiment. Fig.37 As shown, the light deflector 100 - 2B may be formed such that a gap between the fixing unit 108 and the supporting parts 104 a , 104 b is reduced.

[0238] Fig.38 FIG. 1 is a plan view of a light deflector 100-2C which is a variation of the light deflector 100 according to the first embodiment. Fig.38 As shown, the support portion 104a is preferably fan-shaped, wherein the intersection between the extension line L1a connecting the end of the +Y side connection unit 116 and the extension line L2a connecting the end of the -Y side connection unit 116 is located on the first axis. Similarly, the support portion 104b is preferably fan-shaped, wherein the intersection between the extension line L1b connecting the end of the +Y side connection unit 116 and the extension line L2b connecting the end of the -Y side connection unit 116 is located on the first axis. In the case where the support portions 104a, 104b are formed so that the intersection between the extension line connecting the end of the +Y side connection unit 116 and the extension line connecting the end of the -Y side connection unit 116 is located on the first axis, the movable unit 103 can be stably swung around the first axis.

[0239] Fig.39 FIG. 1 is a plan view of a light deflector 100-2D which is a variation of the light deflector 100 according to the first embodiment. Fig.38 As shown, the light deflector 100-2D is formed so that, in the support parts 104a, 104b, the intersection point between the extension line L1 connecting the ends of the connection units 116 on one side and the extension line L2 connecting the ends of the connection units 116 on the other side coincides with the center of the movable unit 103. Therefore, the movable unit 103 can swing around the first axis in a more stable manner.

[0240] Fig.40 is a plan view of a light deflector 100 - 2E which is a variation of the light deflector 100 according to the first embodiment. Fig.41 FIG. 1 is a plan view of a light deflector 100-2F which is a variation of the light deflector 100 according to the first embodiment. Fig.40 As shown, in this embodiment, the movable unit 103 is formed in a substantially rectangular shape, and the beam unit 115 is formed in a straight line shape extending in the Y direction. Fig.41 FIG. 1 is a plan view of a light deflector 100-2F which is a variation of the light deflector 100 according to the first embodiment. Fig.41As shown in FIG. 1 , some parts of the beam unit 115 are formed into a straight line shape extending in the Y direction, and other parts of the beam unit 115 are formed into an arc shape, the center of which coincides with the center of the movable unit 103. Even with such a structure, the beam unit 115 closer to the fixed unit 108 is longer than the beam unit 115 closer to the movable unit 103, and the beam unit 115 closer to the movable unit 103 is also lighter than the beam unit 115 closer to the fixed unit 108. Therefore, the entire length of the support parts 104a, 104b constituting the actuator is increased, and the weight of the beam unit 115 closer to the movable unit 103 is lighter. Therefore, a large scanning angle can be obtained, and the mechanical strength against resonance is improved.

[0241] Fig.42 FIG. 1 is a plan view of a light deflector 100-2G which is a variation of the light deflector 100-2 according to the second embodiment. Fig.42 As shown, the light deflector 100 - 2G may include a single support portion 104 a disposed between the fixed unit 108 and the movable unit 103 for supporting the movable unit 103 .

[0242] Fig.43 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100-2 of the second embodiment. Fig.43 As shown, the light deflector includes three supporting portions, ie, supporting portions 104 c , 104 d , and 104 e , disposed between the fixed unit 108 and the movable unit 103 and used to support the movable unit 103 . Fig.44 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100-2 of the second embodiment. Fig.44 As shown, the optical deflector may include four supporting parts, ie, supporting parts 104f, 104g, 104h, and 104i, disposed between the fixed unit 108 and the movable unit 103 for supporting the movable unit 103. Fig.43 and Fig.44 In the light deflector shown, the deflection direction of light is not limited to a single axis. Light can be deflected in multiple axial directions.

[0243] Fig.45 FIG. 1 is a plan view of a light deflector 150-2 according to a variation of the light deflector 100-2 of the second embodiment. Fig.45 As shown, the light deflector 150-2 is a dual-axis light deflector.

[0244] In such Fig.45In the light deflector 150-2 shown, a movable unit 153 including a reflector unit 101 and a mirror reflecting surface 102 is supported by support portions 104a, 104b constituting a pair of actuators. One end of the movable unit 153 is connected to the reflector unit 101, and the other end of the movable unit 153 is connected to movable unit beams 157a, 157b. The light deflector 150-2 includes torsion beams 156a, 156b supporting the reflector unit 101, so that the reflector unit 101 is between the torsion beams 156a, 156b in the second axial direction. Both ends of the movable unit beams 157a, 157b are connected to the inner side of the movable unit 153 in a frame shape.

[0245] In such Fig.45 In the optical deflector 150-2 shown, the movable unit 153 is supported in such a manner that the movable unit 153 can be resonantly driven by the movable unit beams 157a, 157b. For example, when the torsional resonance frequency of the torsional beams 156a, 156b is set to about 20kHz, a driving signal near the resonance frequency is input to a piezoelectric drive unit disposed on the +Z surface of the movable unit beams 157a, 157b connected to the torsional beams 156a, 156b. As a result, the movable unit beams 157a, 157b vibrate to cause a torsion of mechanical resonance in the torsional beams 156a, 156b, so that the movable unit beams 157a, 157b can rotate the reflector unit 101 around the second axis. In addition, by combining this vibration around the second axis with the swing of the movable unit 103 around the first axis realized by the support parts 104a, 104b of the zigzag structure, Lissajous scanning and raster scanning can be performed.

[0246] With this dual-axis optical deflector, even if the vibration generated by the supporting portions 104a, 104b propagates to the movable unit beams 157a, 157b, in the supporting portions 104a, 104b, the beam unit 115 closer to the movable unit 153 is shorter and less likely to deform than the beam unit 115 closer to the fixed unit 108. Therefore, the vibration of the beam unit 115 in the supporting portions 104a, 104b has less influence on the movable unit beams 157a, 157b.

[0247] In the above description, the piezoelectric layer 132 is provided on the supporting parts 104a and 104b constituting the actuator to realize piezoelectric driving. Fig.45 In the optical deflector 150-2 shown, the support parts 104a and 104b may be deformed under the action of an electromagnetic field to achieve electromagnetic driving, or comb-shaped electrodes may be formed in the support parts 104a and 104b. Coils or magnet arrays may be formed on the support parts 104a and 104b constituting the beam. The support parts 104a and 104b may be driven by resonant driving or non-resonant driving.

[0248] <Variation of the Second Embodiment>

[0249] A light deflector (ie, movable device) according to a variation of the second embodiment will be described below. In the variation of the second embodiment, in the beam unit of the support portion, not only the length but also the thickness and the width are changed.

[0250] Fig.46 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100-2 of the second embodiment. Fig.46 As shown, the planar shape of the light deflector of this embodiment is similar to Fig.33 The planar shapes of the light deflectors shown are the same. Each of the support portions 204a, 204b provided on both sides of the movable unit 103 in the X direction includes a beam unit 215a closer to the movable unit 103 and a beam unit 215b closer to the fixed unit 108. The beam unit 215b is thicker than the beam unit 215a.

[0251] Fig.47 It is along Fig.46 The cross-sectional view is taken along the dotted line 31A-31B. Fig.47 As shown, the two beam units 215b closer to the fixed unit 108 are formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 on the +Z surface of the silicon layer 130. A silicon oxide layer 231 and a silicon layer 232 are sequentially stacked on the -Z surface of the silicon layer 130, and the thickness of the stacked silicon layer 232 is, for example, 30 microns to 40 microns. The two beam units 215a closer to the movable unit 103 are formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 on the +Z surface of the silicon layer 130, but the beam unit 215a does not include the silicon oxide layer 231 and the silicon layer 232 on the -Z surface. Therefore, compared with the first embodiment, the beam unit 215a is lighter than the beam unit 215b. Although Fig.47 A structure having two layers (ie, the silicon oxide layer 231 and the silicon layer 232 ) stacked in sequence is shown, but a single layer may also be formed on the −Z surface of the silicon layer 130 .

[0252] Fig.48 It is along Fig.46 The cross-sectional view taken along the dotted line 31C-31D is shown. Fig.48As shown, the connection unit 216b connecting the two beam units 215b is formed by sequentially stacking a silicon oxide layer 231, a silicon layer 232, a silicon oxide layer 233 and a silicon support layer 234 on the -Z surface of the silicon layer 130. In contrast, in the connection unit 216a connecting the two beam units 215a, no material is provided on the -Z surface of the silicon layer 130. In this way, on the side of the fixed unit 108, a silicon support layer 234 and the like are formed on the rear surface of the connection unit connecting the beam units constituting the zigzag structure, and it is known that this is effective in reducing the vibration of unnecessary natural modes and improving the deflection efficiency of each beam unit. Therefore, the thickness of the silicon support layer 234 and the like closer to the fixed unit 108 is greater than the thickness of the silicon support layer 234 and the like closer to the movable unit 103, thereby further enhancing the effect of the present disclosure.

[0253] Although Fig.48 A structure is shown in which a plurality of layers (i.e., silicon oxide layer 231, silicon layer 232, silicon oxide layer 233, and silicon support layer 234) are sequentially formed on the rear surface of the connection unit, but a single layer may be formed on the rear surface of the connection unit. In this case, when there are many beam units, the thickness of the layer formed on the rear surface of the connection unit may be relatively increased toward the fixed unit 108 and relatively decreased toward the movable unit 103.

[0254] Fig.49 FIG. 2 is a schematic diagram of an example of a connection unit having different curvature radii at the corner according to a variation of the second embodiment. Fig.49 As shown, the curvature radius of the corner 217a of the connection unit 216a closer to the movable unit 103 may be formed to be larger than the curvature radius of the corner 217b of the connection unit 216b closer to the fixed unit 108. As the curvature radius of the corner increases, the size of the cutout for forming the corner also increases, and thus the weight can be reduced.

[0255] Fig.50 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100-2 of the second embodiment. Fig.50As shown, the width of the beam unit 225 in the support parts 214a, 214b supporting the movable unit 103 from both sides of the movable unit 103 in the X direction increases from the movable unit 103 to the fixed unit 108. When the width of the beam unit 225 increases, the weight increases. Specifically, from the movable unit 103 to the fixed unit 108, the length of the beam unit 225 in the support parts 214a, 214b gradually increases, and the width of the beam unit 225 in the support parts 214a, 214b gradually increases. Therefore, in the support parts 214a, 214b, the weight of the beam unit 225 closer to the fixed unit 108 is greater than the weight of the beam unit 225 closer to the movable unit 103, and the effect of the present disclosure can be further enhanced.

[0256] Fig.51 FIG. 1 is a plan view of a light deflector according to a variation of the light deflector 100-2 of the second embodiment. Fig.51 As shown, the connection unit 316b connecting the beam unit 115 closer to the fixed unit 108 may be formed to be wider than the connection unit 316a connecting the beam unit 115 closer to the movable unit 103. In this way, among the connection units connecting the beam units constituting the meandering structure, the width of the connection unit 316b closer to the fixed unit 108 is greater than the width of the connection unit 316a closer to the movable unit 103. Therefore, the effect of the present disclosure can be further enhanced.

[0257] <Third Embodiment>

[0258] The optical deflector 100-3 (i.e., movable device) of the third embodiment will be described below. The configuration of the optical deflector 100-3 is similar to that of the optical deflector 100 of the first and second embodiments, except that the beam unit 115 is formed in a shape different from that of the first and second embodiments, as described below. In the third embodiment, the constituent elements corresponding to those of the first and second embodiments are denoted by the same reference numerals as those of the first and second embodiments, and the corresponding repeated descriptions are appropriately omitted. In addition, when necessary, the drawings referred to in the first and second embodiments are referred to in the third embodiment.

[0259] Before describing the optical deflector 100-3 of the third embodiment, the technology related to the third embodiment is described below. In recent years, with the development of micro-machining technology, the development of MEMS (micro-electromechanical system) devices has made progress. For example, an example of a known MEMS device includes a movable device described in PTL 1. A two-dimensional optical deflection device and an image display device are implemented using this movable device. In order to improve the mechanical drive sensitivity and obtain a large scanning angle using an optical deflector (an example of a movable device), it is conceivable to increase the length of the beam unit used as a vibration beam constituting a zigzag structure. However, when the length of the beam unit used as a vibration beam is increased, there is a problem that the natural resonance frequency of the entire actuator is reduced, thereby reducing the mechanical strength and being prone to vibration, and there is another problem that it is difficult to reduce the size of the movable device.

[0260] First, a uniaxial light deflector (ie, movable device) will be described. Fig.15 900 is a plan view of a light deflector 900, which is a double-end support type and can swing around a first axis. Fig.15 As shown, for example, the light deflector 900 includes a circular reflector unit 901, a mirror reflection surface 902 formed on the +Z surface of the substrate of the reflector unit 901, etc. For example, the reflector unit 901 is made of a silicon layer. The reflector unit 901 can be made of an oxide material, an inorganic material or an organic material, for example. The reflector unit 901 can be made of a plurality of materials or a multilayer composed of the same material, for example. The mirror reflection surface 902 is made of a metal film or a multilayer film containing aluminum, gold, silver, etc., for example. A rib structure for strengthening the reflector unit can be formed on the -Z surface of the substrate of the reflector unit 901. The rib is made of a silicon support layer and a silicon oxide layer, for example, and reduces the distortion of the reflector unit 901 and the mirror reflection surface 902 caused by movement.

[0261] The movable unit 903 including the reflector unit 901 and the mirror reflecting surface 902 is rotatably supported by the supporting parts 904a and 904b constituting a pair of actuators. Specifically, one end (first end) of each of the supporting parts 904a and 904b is connected to the movable unit 903 via the movable unit connecting unit 905. The other end (second end) of each of the supporting parts 904a and 904b opposite to the end is connected to the fixing unit 908.

[0262] exist Fig.15In the embodiment, the fixing unit 908 is formed in a frame shape, but the fixing unit 908 does not necessarily have to be formed in a frame shape. The fixing unit 908 may have an actuator for applying deformation to the fixing unit 908, or may be connected to an actuator for moving the fixing unit 908. The supporting parts 904a, 904b are provided with a plurality of beam units 915 extending in the Y direction. Adjacent beam units 915 are connected by connection units 916 alternately arranged on the +Y side and the -Y side to form a zigzag structure.

[0263] Specifically, the support portions 904a, 904b have a zigzag structure (bellows structure) in which the beam unit 915 extending in the Y direction is connected by a connecting unit 916 so that the beam unit 915 is folded back. Piezoelectric drive unit groups 925A and piezoelectric drive unit groups 925B are alternately provided on the +Z surface of each beam unit 915. The fixed unit 908 is provided with an electrical contact electrode terminal 909. An electric wire (not shown) is provided to connect the electrical contact electrode terminal 909 to the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B. A voltage signal is input to the electrical contact electrode terminal 909 to apply the voltage signal to the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B via the electric wire, so that the movable unit 903 including the reflector unit 901 can be moved around the first axis (i.e., Figure 1 X-axis) rotation.

[0264] In the light deflector 900 , the lengths of the beam units 915 in the Y direction are formed to be substantially the same as each other, and the +Y end and the −Y end of the beam unit 915 are aligned in the X-axis direction.

[0265] Fig.16 It is along Fig.15 1A-1B of the cross-sectional view taken along the dotted line 1A-1B of FIG. The beam unit 915 of the support portion 904a having a zigzag structure and the substrate of the movable unit connection unit 905 are made of an elastic silicon layer 930. In addition, the beam unit 915 and the substrate of the movable unit connection unit 905 have rigidity and can be made of any material that can be processed by a semiconductor process, such as an inorganic material, an organic material, a metallic glass, etc. Alternatively, the beam unit 915 and the substrate of the movable unit connection unit 905 may have a multilayer structure including a plurality of layers made of a plurality of materials.

[0266] The piezoelectric drive unit constituting the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B is formed by sequentially stacking a lower electrode 931, a piezoelectric layer 932 and an upper electrode 933 on the +Z surface of the elastic silicon layer 930. The lower electrode 931 and the upper electrode 933 are made of, for example, gold (Au) or platinum (Pt). The piezoelectric layer 932 is made of, for example, PZT (lead zirconate titanate) (i.e., a piezoelectric material). However, the piezoelectric layer 932 may also be made of other piezoelectric materials and is not limited to any specific type. The piezoelectric drive unit may have a structure including a plurality of stacked piezoelectric layers and including an intermediate electrode. The piezoelectric drive unit is a piezoelectric actuator electrically connected to an external control device and is configured to be driven by applying a voltage. The piezoelectric drive unit in the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B may be covered with an insulating film (not shown) made of silicon oxide, etc., and an electric wire may be formed on the +Z surface of the insulating film.

[0267] The movable unit connection unit 905 includes a silicon layer 930, an interlayer film 941 stacked on the -Z surface of the silicon layer 930, and a support layer 942. The interlayer film 941 is formed of an insulating film (e.g., silicon oxide). The support layer 942 is made of single crystal silicon, but the support layer 942 is not limited to silicon as long as the support layer 942 can support the silicon layer 930 and keep the silicon layer 930 fixed in place. An insulating film and a wire (not shown) may be formed on the +Z surface of the movable unit 903, the connection unit 916, and the movable unit connection unit 905.

[0268] In having Fig.15 In the uniaxial optical deflector of the structure shown, voltage is applied to the piezoelectric drive units in the piezoelectric drive unit group 925A and the piezoelectric drive unit group 925B, so that the movable unit 903 can rotate around the first axis.

[0269] In order to improve Fig.15 The deflection angle of the reflector in the uniaxial optical deflector of the structure shown can be conceived by increasing the length of the beam unit 915 used as a vibration beam constituting the meander structure. However, when the length of the beam unit 915 used as a vibration beam is increased, the natural resonance frequency of the entire actuator is reduced. Therefore, the mechanical strength is reduced and it is easy to shake.

[0270] Therefore, there is a need for an optical deflector that can mitigate the reduction in natural resonance frequency and achieve a large scanning angle.

[0271] Next, the biaxial light deflector will be described. Fig.17950 is a plan view of a light deflector 950 that is a double-end support type and can swing around a first axis and a second axis. In a dual-axis light deflector, the light deflector 950 is generally driven to swing around one axis under resonant vibration at a mechanical resonance frequency, and is generally driven to swing around the other axis under non-resonant vibration.

[0272] In such Fig.17 In the light deflector 950 shown, a movable unit 953 including a reflector unit 901 and a mirror reflecting surface 902 is supported by support portions 904a, 904b constituting a pair of actuators. One end of the movable unit 953 is connected to the reflector unit 901, and the other end of the movable unit 953 is connected to movable unit beams 957a, 957b. The light deflector 950 includes torsion beams 956a, 956b supporting the reflector unit 901, so that the reflector unit 901 is between the torsion beams 956a, 956b in the second axial direction. Both ends of the movable unit beams 957a, 957b are connected to the inner side of the movable unit 953 in a frame shape, so that the torsion beams 956a, 956b are between the movable unit beams 957a, 957b.

[0273] For example, in the case where the torsional resonance frequency of the torsional beams 956a, 956b is set to about 20kHz, a driving signal near the resonance frequency is input to the piezoelectric driving unit provided on the +Z surface of the movable unit beams 957a, 957b connected to the torsional beams 956a, 956b. As a result, the movable unit beams 957a, 957b vibrate to induce a torsion of mechanical resonance in the torsional beams 956a, 956b, so that the movable unit 953 can be moved around the second axis (i.e., Figure 1 In addition, by combining this vibration around the second axis with the swing of the movable unit 953 around the first axis using the support parts 904a, 904b of the zigzag structure, Lissajous scanning and raster scanning can be performed.

[0274] I also hope that Fig.17 The dual-axis optical deflector 950 shown can mitigate the reduction of the natural resonant frequency and achieve a large scanning angle.

[0275] (Light Deflector)

[0276] Next, a light deflector 100 - 3 (ie, movable device) of the third embodiment will be described. Fig.52 1 is a plan view of the light deflector 100-3, which is a double-end support type and can make the movable unit 103 rotate around the first axis (rotation axis) (ie, Fig.52 The light deflector 100 of this embodiment is as follows Fig.52The single-axis light deflector shown.

[0277] like Fig.52 As shown, for example, the light deflector 100 includes a circular reflector unit 101, a mirror reflection surface 102 formed on the +Z surface of the substrate of the reflector unit 101, etc. For example, the reflector unit 101 is made of a silicon layer. The reflector unit 101 can be made of an oxidized material, an inorganic material, or an organic material. The reflector unit 101 can be made of multiple materials or multiple layers of the same material.

[0278] The mirror reflection surface 102 is made of, for example, a metal thin film or a multilayer film including aluminum, gold, silver, etc. A rib structure for reinforcing the mirror unit may be formed on the -Z surface of the substrate of the mirror unit 101. The rib is made of, for example, a silicon support layer and a silicon oxide layer, and reduces the distortion of the mirror unit 101 and the mirror reflection surface 102 caused by movement.

[0279] The movable unit 102, which is substantially circular and includes a reflector unit 103 and a mirror reflecting surface 101, is rotatably supported by support parts 104a, 104b constituting a pair of actuators. Specifically, one end (first end) of each of the support parts 104a, 104b is connected to the movable unit 103 via a movable unit connecting unit 105. The other end (second end) of each of the support parts 104a, 104b opposite to the end is connected to a fixing unit 108.

[0280] exist Fig.52 In the embodiment, the fixing unit 108 is formed in a frame shape, but the fixing unit 108 does not necessarily have to be formed in a frame shape. The support parts 104a, 104b are provided with a plurality of beam units 115. Adjacent beam units 115 are connected by connection units 116 alternately arranged on the +Y side and the -Y side to form a zigzag structure.

[0281] It should be noted that the reflector unit 101 and the movable unit 103 may be formed into an ellipse or a polygon. In the support parts 104a, 104b, the connection unit 116 connecting the adjacent beam units 115 does not have to connect the ends of the adjacent beam units 115 in the longitudinal direction, but may connect the parts closer to the center part than the ends of the adjacent beam units 115 in the longitudinal direction.

[0282] The support parts 104a, 104b include: a plurality of beam units 115 used as vibration beams; and a connection unit 116 connecting adjacent beam units 115. The support parts 104a, 104b have two beam unit groups with different characteristics. The two beam unit groups are obtained by dividing the support parts 104a, 104b at predetermined or given parts.

[0283] Specifically, the support portion 104a includes: a first beam unit group 141a, which is a beam unit group closer to the fixed unit 108; and a second beam unit group 141b, which is a beam unit group closer to the movable unit 103. The support portion 104b includes: a first beam unit group 142a, which is a beam unit group closer to the fixed unit 108; and a second beam unit group 142b, which is a beam unit group closer to the movable unit 103.

[0284] The beam units 115 in the first beam unit groups 141 a , 142 a are formed in an arc shape whose center coincides with the center of the substantially circular movable unit 103 , and are formed to have the same width in the Y direction.

[0285] Specifically, if Fig.52 As shown, the line L1 connecting the +Y ends of the plurality of beam units 115 in the first beam unit group 141a, 142a is formed to be parallel to the first axis, and the line L2 connecting the -Y ends of the plurality of beam units 115 in the first beam unit group 141a, 142a is formed to be parallel to the first axis. In addition, the line L3 connecting the +Y ends of the connection units 116 connecting the beam units 115 together is formed to be parallel to the first axis, and the line L4 connecting the -Y ends of the connection units 116 connecting the beam units 115 together is formed to be parallel to the first axis.

[0286] In the first beam unit groups 141a and 142a, the curvature radius of the beam unit 115 decreases as the distance from the movable unit 103 decreases. For example, in the first beam unit group 141a, the curvature radius R12 of the beam unit 115 close to the fixed unit 108 and far from the movable unit 103 is greater than the curvature radius R11 of the beam unit 115 close to the movable unit 103.

[0287] Since the widths of the beam units 115 in the Y direction are the same, the length of the beam unit 115 having a small radius of curvature R11 and close to the movable unit 103 is greater than the length of the beam unit 115 having a large radius of curvature R12 and close to the fixed unit 108. In the case where there are three or more beam units 115 in the first beam unit groups 141a, 142a, the length of the beam unit 115 having a smaller radius of curvature and close to the movable unit 103 is greater than the length of the beam unit 115 having a larger radius of curvature and close to the fixed unit 108.

[0288] Longer beam elements 115 are more likely to move, while shorter beam elements 115 have greater stiffness and are less likely to move. In this disclosure, the term "stiffness" refers to the degree of resistance to movement caused by a specific force applied to a beam element. In other words, when a certain force is applied, a beam element with greater stiffness is less likely to move than a beam element with less stiffness.

[0289] Therefore, in the light deflector 100 of this embodiment, the beam units 115 in the first beam unit groups 141a, 142a become shorter as the distance from the movable unit 103 increases, and thus have higher rigidity. Specifically, if the first beam unit groups 141a, 142a are divided into two at a predetermined or given position, the beam unit 115 closer to the movable unit 103 is longer than the beam unit 115 closer to the fixed unit 108, and the beam unit 115 closer to the fixed unit 108 has higher rigidity than the beam unit 115 closer to the movable unit 103.

[0290] When the first beam unit groups 141a, 142a are divided into two at a predetermined or given position, there may be a plurality of beam units 115 in the beam unit group closer to the movable unit 103, and there may be a plurality of beam units 115 in the beam unit group closer to the fixed unit 108. In this case, in the first beam unit groups 141a, 142a, the plurality of beam units 115 in the beam unit group closer to the movable unit 103 are longer than the plurality of beam units 115 in the beam unit group closer to the fixed unit 108, and the plurality of beam units 115 in the beam unit group closer to the fixed unit 108 have higher rigidity than the plurality of beam units 115 in the beam unit group closer to the movable unit 103.

[0291] The beam unit 115 in the second beam unit group 141b, 142b is formed into an arc shape, the center of the arc coincides with the center of the substantially circular movable unit 103, and the length of the beam unit 115 gradually increases from the movable unit 103 to the fixed unit 108. Therefore, in a plan view (i.e., viewed along the Z direction), the shape of the beam unit 115 is an arc shape that bulges from the center of the movable unit 103 toward the fixed unit 108.

[0292] Therefore, the beam unit 115 closer to the fixed unit 108 is longer than the beam unit 115 closer to the movable unit 103 , and the beam unit 115 closer to the movable unit 103 is lighter than the beam unit 115 closer to the fixed unit 108 .

[0293] Specifically, if the second beam unit group 141b, 142b is divided into two at a predetermined or given position, the beam unit 115 closer to the fixed unit 108 is longer than the beam unit 115 closer to the movable unit 103, and the beam unit 115 closer to the movable unit 103 is lighter than the beam unit 115 closer to the fixed unit 108.

[0294] When the second beam unit groups 141b, 142b are divided into two at a predetermined or given position, there may be a plurality of beam units 115 in the beam unit group closer to the movable unit 103, and there may be a plurality of beam units 115 in the beam unit group closer to the fixed unit 108. In this case, in the second beam unit groups 141b, 142b, the plurality of beam units 115 in the beam unit group closer to the fixed unit 108 are longer than the plurality of beam units 115 in the beam unit group closer to the movable unit 103, and the plurality of beam units 115 in the beam unit group closer to the movable unit 103 are lighter than the plurality of beam units 115 in the beam unit group closer to the fixed unit 108.

[0295] The second beam unit groups 141b, 142b are preferably fan-shaped, wherein the intersection point between the extension line L5 connecting the end of the +Y side connection unit 116 and the extension line L6 connecting the end of the -Y side connection unit 116 is located on the first axis. When the second beam unit groups 141b, 142b are formed in a fan-shaped shape (where the intersection point between the extension line connecting the end of the +Y side connection unit 116 and the extension line connecting the end of the -Y side connection unit 116 is located on the first axis), the movable unit 103 can be stably swung around the first axis.

[0296] The second beam unit groups 141b, 142b may be formed so that an intersection point between an extension line L5 connecting the end of the +Y-side connection unit 116 and an extension line L6 connecting the end of the -Y-side connection unit 116 coincides with the center of the movable unit 103. In this case, the movable unit 103 can swing around the first axis in a more stable manner.

[0297] If there is an object reflecting light around the mirror reflection surface 102 of the movable unit 103, the light reflected at the position of the object causes stray light relative to the desired reflected light, which reduces the signal-to-noise ratio. Specifically, the performance of the module including the light deflector 100 is reduced. For example, if the module is an image projection device, the image quality is reduced, and if the module is an optical inspection device, the detection accuracy is reduced.

[0298] Therefore, it is preferred that a gap is provided around the mirror reflection surface 102 of the movable unit 103, in which only the connection unit connected to the beam unit 115 exists. Specifically, in the second beam unit groups 141b, 142b, along the outermost peripheral portion of the movable unit 103, between the outermost peripheral portion of the movable unit 103 and the innermost peripheral portion of the beam unit 115 closest to the movable unit 103, a gap having a substantially constant width is preferably formed. In order not only to avoid stray light but also to reduce production process errors, the gap formed between the outermost peripheral portion of the movable unit 103 and the innermost peripheral portion of the beam unit 115 preferably has a substantially constant width along the outermost peripheral portion of the movable unit 103. In this case, the substantially constant width means that errors such as production variations in semiconductor processes can be tolerated.

[0299] exist Fig.52 In the figure, the movable unit 103 is supported by two support parts 104a and 104b arranged on the +X side and the -X side of the movable unit 103, but as described later, the movable unit 103 can also be supported by a single support part so as to rotate around a first axis, or can be supported by multiple support parts so as to rotate around multiple axes.

[0300] In the above manner, the support portions 104a, 104b have a zigzag structure in which the beam unit 115 is connected by the connecting unit 116 so that the beam unit 115 is folded back. Piezoelectric drive unit groups 125A and piezoelectric drive unit groups 125B are alternately provided on the +Z surface of each beam unit 115. The fixed unit 108 is provided with an electrical contact electrode terminal 109. An electric wire (not shown) is provided to connect the electrical contact electrode terminal 109 to the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B. A voltage signal is input to the electrical contact electrode terminal 109 to apply the voltage signal to the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B via the electric wire, so that the movable unit 103 including the mirror unit 101 can rotate around the first axis.

[0301] Fig.53 It is along Fig.52 4A-4B. The substrate of the beam unit 115 having the support portions 104a, 104b of the zigzag structure is made of an elastic silicon layer 130. In addition, the substrate of the beam unit 115 has rigidity and can be made of any material that can be processed by a semiconductor process, such as an inorganic material, an organic material, a metallic glass, etc. Alternatively, the substrate of the beam unit 115 can have a multilayer structure including a plurality of layers made of a plurality of materials.

[0302] The piezoelectric drive units constituting the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B are formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 on the +Z surface of the elastic silicon layer 133. The lower electrode 131 and the upper electrode 133 are made of, for example, gold (Au) or platinum (Pt). The piezoelectric layer 132 is made of, for example, PZT (lead zirconate titanate) (i.e., a piezoelectric material). However, the piezoelectric layer 132 may also be made of other piezoelectric materials and is not limited to any specific type.

[0303] The piezoelectric drive unit may have a structure including a plurality of stacked piezoelectric layers and including an intermediate electrode. The piezoelectric drive unit is a piezoelectric actuator electrically connected to an external control device and configured to be driven by applying a voltage. The +Z side of the piezoelectric drive unit in the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B may be covered with an insulating film (not shown) made of silicon oxide or the like, and an electric wire may be formed on the +Z surface of the insulating film.

[0304] exist Fig.52 In the embodiment, the piezoelectric driving unit is disposed on a portion of the beam unit 115, but the piezoelectric driving unit does not necessarily have to be disposed on a portion of the beam unit 115. Fig.15 As shown, the piezoelectric drive unit may be disposed on the entire surface of the beam unit 915. In addition, the piezoelectric drive unit does not necessarily have to be disposed on all beam units 115. That is, the piezoelectric drive unit may also be disposed on only some of the beam units 115.

[0305] The movable unit connection unit 105 includes a silicon layer 130; and an interlayer film and a silicon support layer stacked in sequence on the -Z surface of the silicon layer 130. The interlayer film is formed by an insulating film (e.g., silicon oxide). The support layer is made of single crystal silicon, but the support layer is not limited to silicon as long as the support layer can support the silicon layer and keep the silicon layer fixed in place. An insulating film and a wire (not shown) may be formed on the +Z surface of the movable unit 103, the connection unit 116, and the movable unit connection unit 105.

[0306] In having Fig.52 In the uniaxial optical deflector of the structure shown, voltage is applied to the piezoelectric drive units in the piezoelectric drive unit group 125A and the piezoelectric drive unit group 125B, so that the movable unit 103 can rotate around the first axis.

[0307] like Fig.52 As shown, in this embodiment, the light deflector 100 is formed in a point-symmetrical manner with respect to the center of the movable unit 103. Alternatively, for example, the light deflector 100 may also be formed in a line-symmetrical manner with respect to a straight line perpendicular to the first axis and passing through the center of the movable unit 103.

[0308] In the case where the light deflector 100 is formed in a linearly symmetrical form, the fixed ends of the zigzag structure on both sides of the movable unit 103 and the movable unit connecting units on both sides of the movable unit 103 are arranged so that the rotation axis (i.e., the first axis) is not between the fixed ends and the movable unit connecting units (i.e., the fixed ends are arranged parallel to the rotation axis, and the movable unit connecting units are arranged parallel to the rotation axis), so that the rotation axis of the natural resonance mode is not easily tilted. Therefore, even when the deflection angle increases, the rotation axis is not easily offset. In addition, the light deflector 100 formed in a linearly symmetrical form is preferred because the component in the direction perpendicular to the desired rotation axis (i.e., crosstalk) can be reduced.

[0309] However, in the case where the light deflector 100 is formed in a line-symmetrical form, the mirror reflection surface 102 of the movable unit 103 may be tilted even in a natural mode in which the entire structure including the movable unit 103 and the meander structure is translated in the Z direction. In other words, the mirror reflection surface 102 tends to rotate in response to the disturbing vibration, and therefore, an unexpected vibration component may be superimposed on the optical scanning, and the light deflector 100 may be damaged by a sudden impact. However, if it is desired to efficiently move the movable unit 103 using external vibration (for example, using a power generation device), the above-mentioned feature is advantageous.

[0310] In contrast, in the case where the light deflector 100 is formed in a point-symmetrical form, the fixed ends of the zigzag structure on both sides of the movable unit 103 and the movable unit connecting units on both sides of the movable unit 103 are arranged so that the rotation axis (i.e., the first axis) is located between the fixed ends and between the movable unit connecting units (i.e., the fixed ends are arranged to straddle the rotation axis, and the movable unit connecting units are arranged to straddle the rotation axis), so that the reflector does not rotate in response to interfering vibrations and can resist sudden impacts. On the other hand, since the movable unit connecting unit is not parallel to the rotation axis, the rotation axis of the natural resonance mode may be easily tilted. Therefore, as the deflection angle increases, the rotation axis may tilt accordingly.

[0311] That is, since point symmetry and line symmetry have their own advantages and disadvantages, it is preferred to selectively use point symmetry and line symmetry according to the purpose. For example, point symmetry is preferred for improving vibration resistance against interference, and line symmetry is preferred for improving the deflection angle of the mirror reflection surface 102 of the movable unit 103.

[0312] Thus, in this embodiment, in the first beam unit groups 141a, 142a, the beam units 115 closer to the fixed unit 108 are shorter and have higher rigidity than the beam units 115 closer to the movable unit 103. In this embodiment, in the second beam unit groups 141b, 142b, the beam units 115 closer to the fixed unit 108 are longer than the beam units 115 closer to the movable unit 103, and the beam units 115 closer to the movable unit 103 are lighter than the beam units 115 closer to the fixed unit 108.

[0313] Therefore, the entire length of the support parts 104a and 104b constituting the actuator is increased, and the weight of the beam unit 115 closer to the movable unit 103 is lighter. Therefore, a large scanning angle can be obtained, and the mechanical strength against resonance is improved. In the first beam unit group 141a and 142a, the stiffness of the beam unit 115 closer to the fixed unit 108 is higher. Therefore, a large scanning angle can be obtained, and the mechanical strength against resonance is improved. It should be noted that, compared with the case where the stiffness of the beam unit 115 closer to the movable unit 103 is higher than the stiffness of the beam unit 115 closer to the fixed unit 108, the mechanical strength against resonance is higher when the stiffness of the beam unit 115 closer to the fixed unit 108 is higher than the stiffness of the beam unit 115 closer to the movable unit 103.

[0314] In the following, it is assumed that a structure is adopted in which the support portion is composed only of the second beam unit group 141b, 142b without the first beam unit group 141a, 142a, so that the second beam unit group 141b, 142b can have more beam units 115. Even in this case, in the second beam unit group 141b, 142b, the beam unit 115 closer to the movable unit 103 is also lighter than the beam unit 115 closer to the fixed unit 108, so this situation is also advantageous in obtaining a large scanning angle. However, in this case, as the distance to the fixed unit 108 decreases, the length of the beam unit 115 increases. Accordingly, the length of the support portion in the Y direction increases, and the overall size of the light deflector increases. In addition, the ineffective area near the movable unit 103 increases, and the area efficiency decreases.

[0315] In contrast, in this embodiment, the first beam unit group 141a, 142a including the beam unit 115 is provided between the fixed unit 108 and the second beam unit group 141b, 142b, and the length of the beam unit 115 decreases as the distance to the fixed unit 108 decreases. Therefore, even when the number of beam units 115 in the first beam unit group 141a, 142a increases, the ineffective area near the movable unit 103 does not increase, and the size of the entire light deflector can be reduced. In other words, according to this embodiment, the light deflector achieves a large scanning angle, and further, the size of the light deflector can be reduced.

[0316] In this embodiment, the number of beam units of the first beam unit group 141a, 142a and the second beam unit group 141b, 142b can be appropriately determined and is not limited to Fig.52 The example shown. The ratio of the number of beam units in the first beam unit group 141a, 142a and the ratio of the number of beam units in the second beam unit group 141b, 142b can be appropriately determined, but the ratio of the number of beam units in the first beam unit group 141a, 142a and the ratio of the number of beam units in the second beam unit group 141b, 142b are preferably the same, or preferably the ratio of the number of beam units in the first beam unit group 141a, 142a is higher than the ratio of the number of beam units in the second beam unit group 141b, 142b. Specifically, the number of beam units in the first beam unit group 141a, 142a is preferably equal to or greater than the number of beam units in the second beam unit group 141b, 142b.

[0317] This is because, when the ratio of the number of beam units in the second beam unit groups 141b, 142b is high, the bending length (the length of the support portion in the Y direction) becomes too large, which excessively increases the weight of the portion closer to the movable unit 103. For example, in the case where the ratio of the number of beam units in the second beam unit groups 141b, 142b is defined as 1, the ratio of the number of beam units in the first beam unit groups 141a, 142a may be 1 or 2.

[0318] An example of a method for making the rigidity of the beam unit 115 closer to the fixed unit 108 higher than the rigidity of the beam unit 115 closer to the movable unit 103 includes a method for adjusting the physical properties (Young's modulus, Poisson's ratio, density, etc.), width, length, thickness, etc. of the beam unit 115 closer to the fixed unit 108 and the beam unit 115 closer to the movable unit 103. Alternatively, two or more of the above physical properties may be used in combination. Rigidity increases with increasing width, decreasing length, and increasing thickness. When a protective film and similar materials are formed on the beam unit 115, the physical properties (Young's modulus, Poisson's ratio, density, etc.), width, length, thickness, etc. of the protective film may be adjusted.

[0319] In this embodiment, the support portions 104a, 104b preferably have a zigzag structure because this can efficiently accumulate the position displacement of multiple beam units. When using a zigzag structure, piezoelectric drive is ideal because the actuator can be efficiently arranged in the beam unit. Therefore, the increase in the size of the entire optical deflector can be alleviated. For example, in electrostatic drive, the comb electrodes are arranged on the periphery of the beam unit, so that the size of the entire optical deflector may increase. In electromagnetic drive, it is difficult to wire multiple beam units and it is difficult to arrange magnets for applying a magnetic field to the beam unit, so the size of the entire optical deflector may increase.

[0320] Fig.54 It shows that Fig.15 The light deflector shown in FIG. Fig.52 The relationship between the resonance frequency of the first mode and the deflection angle of the reflector (i.e., the swing angle of the movable unit 103) in the light deflector of this embodiment is shown. The resonance frequency of the first mode is the lowest resonance frequency among the resonance frequencies. The deflection angle of the reflector corresponds to the scanning angle of the reflector. Fig.54 As shown, in Fig.52 In the optical deflector of this embodiment shown in FIG. 1 , the resonance frequency of the first mode and the deflection angle of the reflector are both higher than those of the embodiment shown in FIG. Fig.15 The corresponding values ​​in the light deflector are shown.

[0321] As described above, in the light deflector 100 of this embodiment, the line L1 connecting the +Y ends of multiple beam units 115 in the first beam unit group 141a, 142a is formed to be parallel to the first axis, and the line L2 connecting the -Y ends of multiple beam units 115 in the first beam unit group 141a, 142a is formed to be parallel to the first axis.

[0322] In this way, the width between the first axis and the end of the beam unit 115 in the first beam unit group 141a, 142a that contributes to the rotational moment is constant, so that the rotational force can be efficiently transmitted to the movable unit 103. Specifically, unless the width between the first axis and the end of the beam unit 115 in the first beam unit group 141a, 142a is constant, the vibrations that contribute to the deflection angle in each beam unit 115 will become out of phase, and when the deflection angle increases, these out-of-phase vibrations cause nonlinear vibrations, thereby causing rotational instability. Therefore, in order to stably rotate the movable unit 103 around the first axis, the width between the first axis and the end of the beam unit 115 in the first beam unit group 141a, 142a is preferably constant.

[0323] Fig.55 is a plan view of a light deflector 100 - 3A according to a variation of the light deflector 100 - 3 of the third embodiment. Fig.55The optical deflector 100-3A is similar to Fig.52 The light deflector 100-3A is different from the frame-shaped fixing unit 108 shown in the figure in that the light deflector 100-3A includes the fixing unit 108 having a shape that is appropriately divided so as to form a light transmission area in a direction perpendicular to the swing axis (first axis) of the movable unit 103. With this configuration, even in the case where the light scanning angle caused by the light deflector 100A is large, the scanning light is less likely to be blocked by the frame. The light transmission area may be as follows: Fig.55 The space shown may alternatively be formed by a light-transmitting member (eg glass).

[0324] Fig.56 FIG. 1 is a plan view of a light deflector 100-3B which is a variation of the light deflector 100-3 according to the third embodiment. Fig.56 As shown, the light deflector 100-3B is formed to have a small gap between the fixed unit 108 and the movable unit 103, and a small gap between the fixed unit 108 and the supporting parts 104a, 104b. For example, the gap between the fixed unit 108 and the movable unit 103 and the gap between the fixed unit 108 and the supporting parts 104a, 104b are constant.

[0325] Fig.57 FIG. 1 is a plan view of a light deflector 100-3C which is a variation of the light deflector 100-3 according to the third embodiment. Fig.57 As shown, the first beam unit groups 141a, 142a are formed so that the width in the Y direction between the ends of the beam unit 115 closer to the movable unit 103 is longer, and the width in the Y direction between the ends of the beam unit 115 closer to the fixed unit 108 is shorter. In this case, in the first beam unit groups 141a, 142a, the length of the beam unit 115 closer to the movable unit 103 can be increased more relative to the length of the beam unit 115 closer to the fixed unit 108.

[0326] like Fig.57 As shown, in the first beam unit groups 141a, 142a, the intersection between the extension line L11 connecting the end of the +Y side connection unit 116 and the extension line L12 connecting the end of the -Y side connection unit 116 is located on the first axis. When the first beam unit groups 141a, 142a are formed so that the intersection between the extension line L11 and the extension line L12 is located on the first axis, the movable unit 103 can be stably swung around the first axis.

[0327] Fig.58 FIG. 1 is a plan view of a light deflector 100-3D according to a variation of the light deflector 100-3 of the third embodiment. Fig.58In the light deflector 100-3D shown, the movable unit 103 is substantially rectangular, and in the first beam unit group 141a, 142a and the second beam unit group 141b, 142b, the beam unit 115 is formed into a straight line extending in the Y direction. With this configuration, it is possible to achieve the same Fig.57 The effect is similar to the effect obtained by the light deflector 100-3C.

[0328] exist Fig.58 In the illustrated light deflector 100-3D, in the second beam unit groups 141b and 142b, the intersection point between the extension line L21 connecting the ends of the connection units 116 on one side and the extension line L22 connecting the ends of the connection units 116 on the other side may coincide with the center of the movable unit 103. Therefore, the movable unit 103 can swing around the first axis in a more stable manner.

[0329] Fig.59 FIG. 1 is a plan view of a light deflector 100-3E which is a variation of the light deflector 100-3 according to the third embodiment. Fig.59 The light deflector 100-3E shown is formed so that in the first beam unit group 141a, 142a and the second beam unit group 141b, 142b, the beam unit 115 is formed by connecting a plurality of straight segments and curved segments to form a substantially arc shape as a whole. Alternatively, some parts of the beam unit 115 may be formed into a straight line shape extending along the Y direction, while other parts of the beam unit 115 may be formed into an arc shape, the center of which coincides with the center of the movable unit 103. Therefore, the movable unit 103 can swing around the first axis in a more stable manner.

[0330] Fig.60 FIG. 1 is a plan view of a light deflector 100-3F which is a variation of the light deflector 100-3 according to the third embodiment. Fig.60 In the illustrated light deflector 100 - 3F, the movable unit 103 is supported by a single supporting portion 104 a provided between the fixed unit 108 and the movable unit 103 .

[0331] Fig.61 FIG. 1 is a plan view of a light deflector 100-3G which is a variation of the light deflector 100-3 according to the third embodiment. Fig.61 In the light deflector 100-3G shown, the movable unit 103 is supported by three supporting parts, namely, supporting parts 104c, 104d, and 104e, provided between the fixed unit 108 and the movable unit 103. For example, the supporting parts 104c, 104d, and 104e have the same structure as the supporting parts 104a and 104b.

[0332] Fig.62FIG. 1 is a plan view of a light deflector 100-3H which is a variation of the light deflector 100-3 according to the third embodiment. Fig.62 In the light deflector 100-3H shown, the movable unit 103 is supported by four supporting parts, namely, supporting parts 104f, 104g, 104h, 104i, provided between the fixed unit 108 and the movable unit 103. For example, the supporting parts 104f, 104g, 104h, and 104i have the same structure as the supporting parts 104a, 104b.

[0333] exist Fig.61 The light deflector 100-3G and Fig.62 In the illustrated light deflector 100-3H, the deflection direction of light is not limited to a single axial direction, and light may be deflected in a plurality of axial directions.

[0334] In the above, refer to Fig.61 and Fig.62 The light deflector 100-3G including three supporting portions between the fixed unit 108 and the movable unit 103 and the light deflector 100-3H including four supporting portions between the fixed unit 108 and the movable unit 103 are described. However, five or more supporting portions may be provided.

[0335] Fig.63 FIG. 1 is a plan view of a light deflector 150-3 according to a variation of the light deflector 100-3 of the third embodiment. Fig.63 As shown, the optical deflector 150-3 is a biaxial optical deflector. In the optical deflector 150, a movable unit 153 including a mirror unit 101 and a mirror reflection surface 102 is supported by support portions 104a, 104b constituting a pair of actuators.

[0336] exist Fig.63 In the embodiment, movable unit beams 157a, 157b facing each other (with the reflector unit 101 arranged therebetween) are connected to bridge the inside of the movable unit 153 in a frame shape. Torsion beams 156a, 156b extend from approximately the center of the movable unit beams 157a, 157b in an approximately vertical direction (i.e., X direction) to support the reflector unit 101.

[0337] In such Fig.63 In the light deflector 150-3 shown, the movable unit 153 is supported in such a manner that the movable unit 153 can be resonantly driven by the movable unit beams 157a, 157b. For example, when the torsional resonance frequency of the torsional beams 156a, 156b is set to about 20kHz, a driving signal near the resonance frequency is input to the piezoelectric driving unit provided on the +Z surface of the movable unit beams 157a, 157b connected to the torsional beams 156a, 156b.

[0338] As a result, the movable unit beams 157a, 157b vibrate to induce mechanically resonant torsion in the torsion beams 156a, 156b, so that the movable unit beams 157a, 157b can rotate the mirror unit 101 around the second axis. In addition, by combining this vibration around the second axis with the swing of the movable unit 103 around the first axis using the support portions 104a, 104b of the zigzag structure, Lissajous scanning and raster scanning can be performed.

[0339] With this dual-axis optical deflector, even if the vibration generated by the supporting portions 104a, 104b propagates to the movable unit beams 157a, 157b, in the supporting portions 104a, 104b, the beam unit 115 closer to the movable unit 153 is shorter and less likely to deform than the beam unit 115 closer to the fixed unit 108. Therefore, the vibration of the beam unit 115 in the supporting portions 104a, 104b has less influence on the movable unit beams 157a, 157b.

[0340] In the above description, the piezoelectric layer 132 is provided on the support parts 104a, 104b constituting the actuator to realize piezoelectric driving. However, electromagnetic driving in which the support parts 104a, 104b are deformed by an electromagnetic field or electrostatic driving using comb-shaped electrodes formed in the support parts 104a, 104b may be adopted. A coil or a magnet array may be formed on the support parts 104a, 104b constituting the beam. The support parts 104a, 104b may be driven by resonant driving or non-resonant driving.

[0341] The shape and configuration of the supporting parts 104a, 104b constituting the actuator are not limited. A specific sensor may be formed together with the beam unit. There is no particular limitation on the sensor. Examples of such sensors include displacement detection sensors (e.g., piezoelectric sensors, resistance type strain gauges, etc.) for outputting signals according to deformation, temperature sensors, etc.

[0342] <Variation of the Third Embodiment>

[0343] The following will describe an optical deflector (i.e., movable device) according to a variation of the third embodiment. In the variation of the third embodiment, in the beam unit of the support portion, not only the length but also the thickness and width are changed. In the variation of the third embodiment, the constituent elements corresponding to those of the above-described embodiment are denoted by the same reference numerals, and the corresponding repeated description is appropriately omitted.

[0344] Fig.64 FIG. 2 is a plan view of an optical deflector according to a variation of the optical deflector 100-3 of the third embodiment. The plan view of the optical deflector 200-3 is similar to that of FIG. Fig.52 The planar shapes of the light deflectors 100 - 3 shown are the same.

[0345] Fig.65 It is along Fig.64 The cross-sectional view is taken along the dotted line 16A-16B. Fig.65 As shown, the first beam unit group 141a of the first supporting portion 204a provided in the X direction of the movable unit 103 includes a beam unit 215a closer to the fixed unit 108 and a beam unit 215b closer to the movable unit 103. The beam unit 215a closer to the fixed unit 108 is thicker than the beam unit 215b closer to the movable unit 103. The above description also applies to the first beam unit group 142a of the second supporting portion 204b provided in the X direction of the movable unit 103.

[0346] The second beam unit group 141b of the first supporting portion 204a provided in the X direction of the movable unit 103 includes a beam unit 215c closer to the fixed unit 108 and a beam unit 215d closer to the movable unit 103. The beam unit 215c closer to the fixed unit 108 and the beam unit 215d closer to the movable unit 103 have the same thickness as the beam unit 215b of the first beam unit group 141a. The above description also applies to the second beam unit group 142b of the second supporting portion 204b provided in the X direction of the movable unit 103.

[0347] The beam unit 215a is formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 on the +Z surface of the silicon layer 130. In the beam unit 215a, a silicon oxide layer 231 and a silicon layer 232 are sequentially stacked on the -Z surface of the silicon layer 130. For example, the thickness of the stacked silicon layer 232 is 30 micrometers to 40 micrometers.

[0348] The beam units 215b, 215c, and 215d are formed by sequentially stacking a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 on the +Z surface of the silicon layer 130. However, in the beam units 215b, 215c, and 215d, the silicon oxide layer 231 and the silicon layer 232 are not provided on the -Z surface. In this way, the beam unit 215a is constructed to be shorter and thicker than the beam units 215b, 215c, and 215d. Therefore, compared with the third embodiment, the beam unit 215a has a higher rigidity than the beam units 215b, 215c, and 215d. Fig.65 In the embodiment, two layers are stacked and formed, namely, a silicon oxide layer 231 and a silicon layer 232. However, there may be only one layer.

[0349] Fig.66 It is along Fig.64 The cross-sectional view taken along the dotted line 16C-16D is shown. Fig.66 As shown, the portions of the connecting unit 216a connecting the beam unit 215a and the beam unit 215b located at the longitudinal ends of the beam unit 215a are thicker than the remaining portions of the connecting unit 216a. The portions of the connecting unit 216a located at the longitudinal ends of the beam unit 215a are formed by sequentially stacking a silicon oxide layer 231, a silicon layer 232, a silicon oxide layer 233, and a silicon support layer 234 on the -Z surface of the silicon layer 130, but in the remaining portions of the connecting unit 216a, no layer is provided on the -Z surface of the silicon layer 130. In the connecting unit 216b connecting the beam unit 215c and the beam unit 215d, no layer is provided on the -Z surface of the silicon layer 130.

[0350] It is known that the silicon support layer 234 or the like provided on the rear surface of the connection unit connecting the beam units constituting the meandering structure in this manner is effective in reducing unnecessary vibrations of the natural mode and improving the deflection efficiency of each beam unit. Therefore, the thickness of the connection unit 216a closer to the fixed unit 108 can be configured to be greater than the thickness of the connection unit 216a closer to the movable unit 103, thereby further enhancing the effect of the present disclosure.

[0351] Although Fig.66 A multilayer structure in which a silicon oxide layer 231, a silicon layer 232, a silicon oxide layer 233, and a silicon support layer 234 are sequentially stacked on the rear surface of the connection unit is shown, but there may be only a single layer. In this case, when there are many beam units, the thickness of the layer formed on the rear surface of the connection unit may be relatively increased toward the fixed unit 108 and relatively decreased toward the movable unit 103.

[0352] Fig.67 FIG. 2 is a plan view of a light deflector according to a variation 200-3A of the light deflector 100-3 of the third embodiment. Fig.67 In the light deflector 200-3A shown, in the first beam unit group 141a of the first supporting portion 214a provided in the X direction of the movable unit 103, the width of the beam unit 225 gradually increases from the movable unit 103 to the fixed unit 108. The above description also applies to the first beam unit group 142a of the second supporting portion 214b provided in the X direction of the movable unit 103.

[0353] In this way, in the first beam unit groups 141a and 142a, the width of the beam unit 225 closer to the fixed unit 108 is larger, and thus the rigidity is greater. Specifically, from the movable unit 103 to the fixed unit 108, the length of the beam unit 225 in the first beam unit groups 141a and 142a gradually decreases, and the width of the beam unit 225 in the first beam unit groups 141a and 142a gradually increases. In other words, in the first beam unit groups 141a and 142a, the length of the beam unit 225 closer to the movable unit 103 is larger than the length of the beam unit 225 closer to the fixed unit 108, and the rigidity of the beam unit 225 closer to the fixed unit 108 is higher than the rigidity of the beam unit 225 closer to the movable unit 103. Therefore, the effect of the present disclosure can be further enhanced.

[0354] Fig.68 FIG. 2 is a plan view of a light deflector according to a variation 200-3B of the light deflector 100-3 of the third embodiment. Fig.68 In the light deflector 200-3B shown, in the first beam unit group 141a of the first support portion 224a provided in the X direction of the movable unit 103, the width of the connection unit 316a is increased from the movable unit 103 to the fixed unit 108. The above description also applies to the first beam unit group 142a of the second support portion 224b provided in the X direction of the movable unit 103. In this configuration, in the connection unit 316a connecting the beam units 115 constituting the meander structure in each of the first beam unit groups 141a, 142a, the width of the beam unit 225 closer to the fixed unit 108 is configured to be larger than the width of the beam unit 225 closer to the movable unit 103, so that the rigidity on the fixed unit 108 side is higher than the rigidity on the movable unit 103 side. Therefore, the effect of the present disclosure can be further enhanced.

[0355] When the movable device of the above-described embodiment is used for an optical scanning system, the size of the optical scanning system can be reduced, and the optical scanning system can achieve a large scanning angle.

[0356] When the movable device of the above-described embodiment is used for an image projection device, the size of the image projection device can be reduced, and the image projection device can realize a large projectable area.

[0357] When the movable device of the above-described embodiment is used for an optical writing device, the size of the optical writing device can be reduced, and the optical writing device can realize a large writable area.

[0358] When the mobile device of the above-mentioned embodiment is used for an object recognition device, the size of the object recognition device can be reduced, and the object recognition device can achieve a large recognition range.

[0359] When the movable device of the above-described embodiment is used for a laser headlight, the size of the laser headlight can be reduced, and the laser headlight can realize a large illumination area.

[0360] When the mobile device of the above-described embodiment is used for a head-mounted display, the size of the head-mounted display can be reduced, and the head-mounted display can realize a large imaging area.

[0361] For example, in each of the above-mentioned embodiments, the movable unit includes a reflector unit. The movable unit may also have a diffraction grating, a photodiode, a heater (for example, a heater using SiN), a light source (for example, a surface emitting laser), etc. instead of a reflector unit.

[0362] Although exemplary embodiments of the present disclosure are described above, the present disclosure is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present disclosure described in the claims.

[0363] Reference numerals list

[0364] 10 Optical Scanning System

[0365] 11 Control Device

[0366] 12,12b Light source device

[0367] 13 Mobile devices

[0368] 14 Reflective surface

[0369] 15 Scan Surface

[0370] 25 Light source device driver

[0371] 26 Removable device drivers

[0372] 30 Control unit

[0373] 31. Drive signal output unit

[0374] 50 Laser Headlight

[0375] 51 Reflector

[0376] 52 Transparent Plate

[0377] 60 Head-mounted display

[0378] 60a front

[0379] 60b Temple

[0380] 61 Light guide plate

[0381] 62 Half Mirror

[0382] 63 Wearer

[0383] 100 Light deflector (movable device)

[0384] 101 Mirror unit

[0385] 102 Mirror Reflection Surface

[0386] 103 Mobile Units

[0387] 104a, 104b Supporting part

[0388] 105 Movable unit connection unit

[0389] 108 Fixed Unit

[0390] 109 Electrical contact electrode terminal

[0391] 115 Beam element

[0392] 116 Connection unit

[0393] 125A,125B Piezoelectric drive unit set

[0394] 130 Silicon layer

[0395] 131 Lower electrode

[0396] 132 Piezoelectric layer

[0397] 133 Upper electrode

[0398] 400 Car (an instance of a vehicle)

[0399] 500 Head-up display device (an example of an image projection device, an example of a head-up display)

[0400] 600 Writing device

[0401] 650 Laser Printer

[0402] 700 LiDAR device (an example of an object recognition device)

[0403] 702 Target Object

[0404] 801 Encapsulation Components

[0405] 802 Attachment member

[0406] 803 Transparent Components

[0407] Reference List

[0408] Patent Literature

[0409] [PTL 1] Unexamined Japanese Patent Application Publication No. 2014-232176

[0410] This application is based on and claims the benefit of priority of Japanese Priority Application No. 2019-190737 filed on October 18, 2019, Japanese Priority Application No. 2019-190738 filed on October 18, 2019, and Japanese Priority Application No. 2020-045695 filed on March 16, 2020, the contents of which are incorporated herein.

Claims

1. A movable device, comprising: a movable unit including a reflector configured to reflect light; a support portion including a first end and a second end, the first end being connected to the movable unit, and the support portion being configured to swingably support the movable unit; as well as a fixing unit connected to the second end of the supporting portion, The support portion comprises: multiple beam elements; and at least one connecting unit connecting adjacent beam units of the plurality of beam units, Wherein, in the case where the support portion is divided into two parts at a predetermined or given position, and the two parts include a first part closer to the fixed unit and a second part closer to the movable unit, In the plurality of beam units including more than two beam units, the lengths of the plurality of beam units gradually decrease from the movable unit to the fixed unit, the beam units in the first portion have higher rigidity than the beam units in the second portion, and The beam elements in the second portion are longer than the beam elements in the first portion, The plurality of beam units are arranged adjacent to each other in such an order that a beam unit close to the fixed unit side is shorter in length and higher in rigidity than a beam unit close to the movable unit side. 2 . The movable device of claim 1 , wherein a thickness of the beam unit in the first portion is greater than a thickness of the beam unit in the second portion.

3. The mobile device according to claim 1 or 2, wherein the at least one connection unit comprises: a first connecting unit connecting adjacent beam units in a first portion of the plurality of beam units; and a second connecting unit connecting adjacent beam units in a second part among the plurality of beam units, The thickness of the first connection unit is greater than the thickness of the second connection unit. 4 . The movable device according to claim 1 , wherein a width of the beam unit in the first portion is greater than a width of the beam unit in the second portion.

5. The mobile device according to claim 1 or 2, wherein the at least one connection unit comprises: a first connecting unit connecting adjacent beam units in a first portion of the plurality of beam units; and a second connecting unit connecting adjacent beam units in a second part among the plurality of beam units, The width of the first connection unit is greater than the width of the second connection unit.

6. A movable device comprising: Mobile units; a support portion including a first end and a second end, the first end being connected to the movable unit, and the support portion being configured to swingably support the movable unit; as well as a fixing unit connected to the second end of the supporting portion, The support portion comprises: multiple beam elements; and at least one connecting unit connecting adjacent beam units of the plurality of beam units, Wherein, in a case where the support portion is divided into a first part and a second part at a predetermined or given position, and the first part is closer to the fixed unit and the second part is closer to the movable unit, among the plurality of beam units, the beam units in the first part are defined as a first beam unit group, and the beam units in the second part are defined as a second beam unit group, Wherein, in the case where the first beam unit group is divided into a third beam unit group and a fourth beam unit group at a predetermined or given second position, and the third beam unit group is closer to the fixed unit and the fourth beam unit group is closer to the movable unit, Among the plurality of beam elements, the beam elements in the third beam element group have higher rigidity than the beam elements in the fourth beam element group, and The beam elements in the fourth beam element group are longer than the beam elements in the third beam element group, Wherein, in the case where the second beam unit group is divided into a fifth beam unit group and a sixth beam unit group at a predetermined or given third position, and the fifth beam unit group is closer to the fixed unit and the sixth beam unit group is closer to the movable unit, Among the plurality of beam elements, the beam elements in the fifth beam element group are longer than the beam elements in the sixth beam element group, and The beam elements in the sixth beam element group are lighter than the beam elements in the fifth beam element group, wherein the beam units in the first beam unit group are arranged adjacent to each other in such an order that the beam units close to the fixed unit side are shorter in length and larger in rigidity than the beam units close to the movable unit side, The beam units in the second beam unit group are arranged adjacent to each other in such an order that the beam units close to the fixed unit side are longer in length and heavier in weight than the beam units close to the movable unit side. 7 . The movable device according to claim 6 , wherein a thickness of the beam units in the third beam unit group is greater than a thickness of the beam units in the fourth beam unit group.

8. The mobile device according to claim 6 or 7, wherein the at least one connection unit comprises: a first connecting unit connecting adjacent beam units in a third beam unit group among the plurality of beam units; and a second connecting unit connecting adjacent beam units in a fourth beam unit group among the plurality of beam units, The thickness of the first connection unit is greater than the thickness of the second connection unit. 9 . The movable device according to claim 6 , wherein the width of the beam units in the fifth beam unit group is greater than the thickness of the beam units in the sixth beam unit group. 10 . The movable device of claim 6 , wherein the support portion has a shape including an arc, a center of the arc coincides with a center of the movable unit.

11. The mobile device of claim 6, wherein the at least one support portion comprises a first support portion and a second support portion, and The first supporting portion and the second supporting portion support the movable unit from both sides of the movable unit so that the movable unit can rotate around a first axis.

12. The movable device according to claim 6, wherein the movable unit comprises: a first movable unit beam; and a second movable unit beam including a first end connected to the first movable unit beam and a second end connected to the movable unit, The second movable unit beam supports the movable unit so that the movable unit can be resonantly driven.

13. The mobile device of claim 6, wherein the at least one support portion comprises three or more support portions, and The three or more supporting portions support the movable unit so that the movable unit can rotate around a plurality of axes. 14 . The movable device according to claim 6 , wherein one or more beam units among the plurality of beam units are provided with a piezoelectric driving unit.

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