JP2018136403A - Optical deflector, optical scanning device, image projection device, and object recognition device - Google Patents

Abstract

An optical deflector capable of achieving high-quality optical scanning performance while suppressing peeling of a reflective film and breakage of a torsion bar is provided. A mirror portion 101 having a reflecting member 14 for reflecting light and displaceable around an axis O1, a pair of torsion bars 111a and 111b having one end connected to the mirror portion 101 and supporting the mirror portion 101, and a torsion bar. A pair of drive beams 112a and 112b connected to the other ends of the bars 111a and 111b and supporting the torsion bars 111a and 111b in a displaceable manner; has a body portion 14c and projecting portions 14a and 14b projecting from the body portion 14c in the direction of the axis O1. [Selection drawing] Fig. 18

Description

  The present invention relates to an optical deflector, an optical scanning device, an image projection device, and an object recognition device.

In recent years, development of MEMS (Micro Electro Mechanical Systems) devices manufactured by microfabrication of silicon and glass has progressed, and as one of them, a movable part provided with a reflective surface on a substrate and an elastic beam part are integrally formed. A small optical deflector that deflects and scans a light beam has been developed.
As one of the optical deflectors, there is known a piezoelectric optical deflector that employs a piezoelectric actuator system in which a thin piezoelectric material is superimposed on a beam-like elastic member. It is transmitted to the support and the reflecting surface is displaced by vibrating the beam up and down. Further, by providing separate driving piezoelectric bodies for the two axes of the first axis and the second axis orthogonal to each other, different speeds and different driving characteristics can be provided between the two axes.

In the above-described piezoelectric optical deflector, horizontal scanning is driven using mechanical resonance, one end of the beam is fixedly supported on the frame portion, and the other end is vibrated by piezoelectric driving. The torque generated by the vibration of the beam portion is transmitted to a torsion bar which is an elastic beam connected to the other end of the beam, and the mirror member connected to the torsion bar is displaced to perform optical scanning. A reflective film is generally laminated on the mirror member.
With conventional optical deflectors, the stress concentration around the torsion bar and the reflecting mirror increases as the speed increases and the scanning angle increases, increasing the risk of peeling of the reflecting film and breaking the torsion bar. There is a trade-off relationship with the performance improvement, and there is a problem in that when the scanning performance of the optical deflector is improved, the image luminance is lowered and the irradiation beam quality is easily deteriorated during the optical scanning.

Therefore, in order to provide an optical scanning device that can relieve stress applied to the mirror portion and reduce breakage and material fatigue, there is a technology for providing an optical deflector that optimizes the substrate shape of the mirror portion and its optimization. It is disclosed (for example, refer to “Patent Document 1”).
In this technology, a movable frame that supports a mirror part having a mirror reflecting surface from the outside is supported from both sides, and a horizontal drive beam that swings the mirror part around a predetermined axis is provided. By doing so, the stress applied to the mirror portion is relaxed.

However, in the above-described technique, when a plurality of lightening portions are formed on the movable member itself, a portion where the width of the movable member is narrowed is formed at the same time. There is a problem in that the risk of damage to the member increases with the increase in size.
An object of the present invention is to provide an optical deflector capable of solving the above-described problems and realizing high-quality optical scanning performance while suppressing peeling of a reflective film and breakage of a torsion bar.

  The present invention includes a mirror part having a reflecting member that reflects light and being displaceable about an axis, a pair of torsion bars having one end connected to the mirror part and supporting the mirror part, and the other end of the torsion bar. A pair of drive beams that connect and support the torsion bar so as to be displaceable; and a support frame to which the drive beams connect; and the reflection member is formed to project from the main body portion and the main body portion in the axial direction. And a protrusion.

  According to the present invention, since the reflecting member has the protruding portion formed to protrude in the axial direction, the area of the reflecting member is enlarged to improve the film adhesion with the silicon active layer and prevent the reflecting member from being peeled off. In addition, it is possible to provide an optical deflector capable of realizing high-quality optical scanning performance.

It is the schematic of an example of an optical scanning system. It is a hardware block diagram of an example of an optical scanning system. It is a functional block diagram of an example of a drive device. It is a flowchart of an example of the process which concerns on an optical scanning system. It is the schematic of an example of the motor vehicle carrying a head up display apparatus. It is a schematic diagram of an example of a head up display device. It is the schematic of an example of the image forming apparatus carrying an optical writing device. It is the schematic of an example of an optical writing device. It is the schematic of an example of the motor vehicle carrying a laser radar apparatus. It is the schematic of an example of a laser radar apparatus. It is the schematic of an example of the packaged optical deflector. It is a top view which shows an example of a structure of an optical deflector. It is PP sectional drawing of the optical deflector shown in FIG. It is QQ sectional drawing of the optical deflector shown in FIG. (A) The conventional mirror part (b) It is the schematic which shows the mirror part of this invention. (A) AA sectional view (b) BB sectional view shown in FIG. (A) Schematic which shows the displacement state of a mirror part (b) It is the schematic explaining the connection part of a mirror part and a torsion bar. It is the schematic explaining the structure and shape of a mirror part. It is a schematic diagram which shows the drive of the 2nd drive part of an optical deflector. It is the schematic explaining the drive voltage applied to the piezoelectric drive part groups A and B of an optical deflector. (A) Schematic structural drawing of the mirror part used for the 2nd Embodiment of this invention (b) CC sectional drawing of (a) (c) It is a schematic block diagram of the mirror part which shows the modification. It is a schematic block diagram of the mirror part used for the 3rd Embodiment of this invention. It is a schematic block diagram of the mirror part used for the 4th Embodiment of this invention. It is a top view which shows an example of a structure of the other optical deflector which can apply this invention.

Hereinafter, embodiments of the present invention will be described in detail.
[Optical scanning system]
First, an optical scanning system as an optical scanning device to which a driving device according to an embodiment of the present invention is applied will be described in detail with reference to FIGS.
FIG. 1 is a schematic diagram illustrating an example of an optical scanning system. As shown in FIG. 1, the optical scanning system 10 deflects the light emitted from the light source device 12 according to the control of the driving device 11 by the reflecting member 14 of the optical deflector 13 and optically scans the surface to be scanned 15. It is.

The optical scanning system 10 includes a driving device 11, a light source device 12, and an optical deflector 13 having a reflecting member 14.
The drive device 11 is an electronic circuit unit including, for example, a CPU (Central Processing Unit) and an FPGA (Field-Programmable Gate Array). The optical deflector 13 is, for example, a MEMS (Micro Electromechanical Systems) device having a reflective member 14 and capable of displacing the reflective member 14. The light source device 12 is, for example, a laser device that irradiates a laser. The scanned surface 15 is, for example, a screen.
The drive device 11 generates a control command for the light source device 12 and the optical deflector 13 based on the acquired optical scanning information, and outputs a drive signal to the light source device 12 and the optical deflector 13 based on the control command.

The light source device 12 performs light irradiation based on the input drive signal. The optical deflector 13 displaces the reflecting member 14 in at least one of the uniaxial direction and the biaxial direction based on the input drive signal.
Thereby, for example, by the control of the driving device 11 based on image information which is an example of optical scanning information, the reflecting member 14 of the optical deflector 13 is reciprocated in a biaxial direction within a predetermined range and is incident on the reflecting member 14. An arbitrary image can be projected on the scanned surface 15 by deflecting the light emitted from the light source device 12 and performing optical scanning.
Details of the optical deflector 13 and details of control by the driving device 11 of the present embodiment will be described later.

Next, an exemplary hardware configuration of the optical scanning system 10 will be described with reference to FIG.
FIG. 2 is a hardware configuration diagram of an example of the optical scanning system 10.
As shown in FIG. 2, the optical scanning system 10 includes a drive device 11, a light source device 12, and an optical deflector 13, and each is electrically connected.

[Driver]
Among these, the driving device 11 includes a CPU 20, a RAM 21 (Random Access Memory), a ROM 22 (Read Only Memory), an FPGA 23, an external I / F 24, a light source device driver 25, and an optical deflector driver 26.
The CPU 20 is an arithmetic unit that reads programs and data from a storage device such as the ROM 22 onto the RAM 21 and executes processing to realize overall control and functions of the drive device 11.

The RAM 21 is a volatile storage device that temporarily stores programs and data.
The ROM 22 is a nonvolatile storage device that can retain programs and data even when the power is turned off, and stores processing programs and data that the CPU 20 executes to control each function of the optical scanning system 10. Yes.
The FPGA 23 is a circuit that outputs control signals suitable for the light source device driver 25 and the optical deflector driver 26 in accordance with the processing of the CPU 20.
The external I / F 24 is an interface with, for example, an external device or a network. The external device includes, for example, a host device such as a PC (Personal Computer) and a storage device such as a USB memory, an SD card, a CD, a DVD, an HDD, and an SSD. The network is, for example, an automobile CAN (Controller Area Network), LAN (Local Area Network), the Internet, or the like. The external I / F 24 may be configured to enable connection or communication with an external device, and the external I / F 24 may be prepared for each external device.

The light source device triber 25 is an electric circuit that outputs a drive signal such as a drive voltage to the light source device 12 in accordance with an input control signal.
The optical deflector driver 26 is an electric circuit that outputs a drive signal such as a drive voltage to the optical deflector 13 in accordance with the input control signal.
In the driving device 11, the CPU 20 acquires optical scanning information from an external device or a network via the external I / F 24. The CPU 20 may be configured so that the optical scanning information can be acquired. The optical scanning information may be stored in the ROM 22 or the FPGA 23 in the driving device 11, or a new SSD or the like may be included in the driving device 11. A storage device may be provided, and the optical scanning information may be stored in the storage device.

Here, the optical scanning information is information indicating how the scanned surface 15 is optically scanned. For example, when an image is displayed by optical scanning, the optical scanning information is image data. For example, when optical writing is performed by optical scanning, the optical scanning information is write data indicating a writing order and a writing location. In addition, for example, when object recognition is performed by optical scanning, the optical scanning information is irradiation data indicating the timing and irradiation range of irradiation with light for object recognition.
The drive device 11 according to the present embodiment can realize the functional configuration described below by the instruction of the CPU 20 and the hardware configuration shown in FIG.

[Functional configuration of drive unit]
Next, the functional configuration of the driving device 11 of the optical scanning system 10 will be described with reference to FIG. FIG. 3 is a functional block diagram of an example of the driving device 11 of the optical scanning system 10.
As illustrated in FIG. 3, the drive device 11 includes a control unit 30 and a drive signal output unit 31 as functions.
The control unit 30 is realized by, for example, the CPU 20, the FPGA 23, and the like, acquires optical scanning information from an external device, converts the optical scanning information into a control signal, and outputs the control signal to the drive signal output unit 31. For example, the control unit 30 constitutes a control unit, acquires image data as optical scanning information from an external device or the like, generates a control signal from the image data by a predetermined process, and outputs the control signal to the drive signal output unit 31.

The drive signal output unit 31 constitutes application means, and is realized by the light source device driver 25, the optical deflector driver 26, and the like, and outputs a drive signal to the light source device 12 or the optical deflector 13 based on the input control signal. The drive signal output unit 31 (applying means) may be provided for each target that outputs a drive signal, for example.
The drive signal is a signal for controlling driving of the light source device 12 or the optical deflector 13. For example, in the light source device 12, the driving voltage is used to control the irradiation timing and irradiation intensity of light. For example, in the optical deflector 13, the driving voltage is used to control the timing and the movable range at which the reflecting member 14 of the optical deflector 13 is moved. The driving device 11 may acquire the light irradiation timing and the light receiving timing from an external device such as the light source device 12 and the light receiving device, and may synchronize these with the driving of the optical deflector 13.

[Optical scanning processing]
Next, a process in which the optical scanning system 10 optically scans the surface to be scanned 15 will be described with reference to FIG. FIG. 4 is a flowchart of an example of processing according to the optical scanning system 10.
In step S11, the control unit 30 acquires optical scanning information from an external device or the like.
In step S <b> 12, the control unit 30 generates a control signal from the acquired optical scanning information, and outputs the control signal to the drive signal output unit 31.
In step S <b> 13, the drive signal output unit 31 outputs a drive signal to the light source device 12 and the optical deflector 13 based on the input control signal.
In step S <b> 14, the light source device 12 performs light irradiation based on the input drive signal. The optical deflector 13 moves the reflecting member 14 based on the input drive signal. By driving the light source device 12 and the optical deflector 13, light is deflected in an arbitrary direction and optically scanned.

In the optical scanning system 10, one driving device 11 has a device and a function for controlling the light source device 12 and the optical deflector 13, but the driving device for the light source device 12 and the optical deflector 13 are used. The driving device and the driving device may be provided separately.
In the optical scanning system 10, the function of the control unit 30 and the function of the drive signal output unit 31 of the light source device 12 and the optical deflector 13 are provided in one drive device 11, but these functions are separately provided. For example, a drive signal output device having a drive signal output unit 31 may be provided in addition to the drive device 11 having the control unit 30. In the optical scanning system 10, an optical deflection system as an irradiating unit that performs optical deflection may be configured by the optical deflector 13 having the reflecting member 14 and the driving device 11.

[Image projection device]
Next, an image projection apparatus to which the drive device 11 of this embodiment is applied will be described in detail with reference to FIGS. 5 and 6.
FIG. 5 is a schematic diagram according to an embodiment of an automobile 400 equipped with a head-up display device 500 which is an example of an image projection device. FIG. 6 is a schematic diagram of an example of the head-up display device 500.

The image projection device is a device that projects an image by optical scanning, for example, a head-up display device.
As shown in FIG. 5, the head-up display device 500 is installed, for example, in the vicinity of a windshield (a windshield 401 or the like) of the automobile 400. The projection light L emitted from the head-up display device 500 is reflected by the windshield 401 and travels toward an observer (driver 402) who is a user.
Accordingly, the driver 402 can visually recognize an image or the like projected by the head-up display device 500 as a virtual image. In addition, you may make it the structure which installs a combiner in the inner wall face of a windshield, and makes a user visually recognize a virtual image with the projection light reflected by a combiner.

As shown in FIG. 6, the head-up display device 500 emits laser light from red, green, and blue laser light sources 501R, 501G, and 501B. The emitted laser light is transmitted through an incident optical system including collimator lenses 502, 503, and 504 provided for the respective laser light sources, two dichroic mirrors 505 and 506, and a light amount adjusting unit 507 as a combining unit. After that, the light is deflected by the optical deflector 13 having the reflecting member 14.
The deflected laser light is projected onto the screen through a projection optical system including a free-form surface mirror 509, an intermediate screen 510, and a projection mirror 511.

In the head-up display device 500, the laser light sources 501R, 501G, and 501B, the collimator lenses 502, 503, and 504 and the dichroic mirrors 505 and 506 are unitized as an optical housing by an optical housing.
The head-up display device 500 projects the intermediate image displayed on the intermediate screen 510 onto the windshield 401 of the automobile 400 so that the driver 402 can visually recognize the intermediate image as a virtual image.

The respective color laser beams emitted from the laser light sources 501R, 501G, and 501B are made substantially parallel lights by the collimator lenses 502, 503, and 504, respectively, and are combined by the two dichroic mirrors 505 and 506. The combined laser light is subjected to two-dimensional scanning by the optical deflector 13 having the reflecting member 14 after the light amount is adjusted by the light amount adjusting unit 507. The projection light L that has been two-dimensionally scanned by the optical deflector 13 is reflected by the free-form surface mirror 509 and corrected for distortion, and then condensed on the intermediate screen 510 to display an intermediate image.
The intermediate screen 510 includes a microlens array in which microlenses are two-dimensionally arranged, and enlarges the projection light L incident on the intermediate screen 510 in units of microlenses.
The optical deflector 13 reciprocates the reflecting member 14 in the biaxial direction, and two-dimensionally scans the projection light L incident on the reflecting member 14. The drive control of the optical deflector 13 is performed in synchronization with the light emission timings of the laser light sources 501R, 501G, and 501B.

Although the head-up display device 500 as an example of the image projection device has been described above, the image projection device may be any device that projects an image by performing optical scanning with the optical deflector 13 having the reflecting member 14. .
For example, a projector that is placed on a desk or the like and projects an image on a display screen, or a projection member that is mounted on a mounting member that is mounted on an observer's head or the like, is projected on a reflective transmission screen of the mounting member, or an image is projected using an eyeball as a screen. The present invention can be similarly applied to a head mounted display device or the like.
Further, the image projection apparatus is not only a vehicle or a mounting member, but a non-moving body such as a working robot that operates a driving object such as a manipulator without moving from the spot, for example, a moving body such as an aircraft, a ship, or a mobile robot. It may be mounted on.

[Optical writing device]
Next, with reference to FIG. 7 and FIG. 8, an optical writing device to which the driving device 11 of this embodiment is applied will be described in detail.
FIG. 7 is an example of an image forming apparatus incorporating the optical writing device 600. FIG. 8 is a schematic diagram of an example of an optical writing device.
As shown in FIG. 7, the optical writing device 600 is used as a constituent member of an image forming apparatus represented by a laser printer 650 having a printer function using laser light. In the image forming apparatus, the optical writing device 600 performs optical writing on the photosensitive drum by optically scanning the photosensitive drum which is the surface to be scanned 15 with one or a plurality of laser beams.

As shown in FIG. 8, in the optical writing device 600, the laser light from the light source device 12 such as a laser element passes through an imaging optical system 601 such as a collimator lens and is then 1 by an optical deflector 13 having a reflecting member 14. It is deflected axially or biaxially.
Then, the laser beam deflected by the optical deflector 13 passes through the scanning optical system 602 including the first lens 602a, the second lens 602b, and the reflection mirror unit 602c, and then the scanned surface 15 (for example, a photosensitive drum or photosensitive paper). The optical writing is performed. The scanning optical system 602 forms a light beam in a spot shape on the scanned surface 15.
The light deflector 13 having the light source device 12 and the reflecting member 14 is driven based on the control of the driving device 11.

As described above, the optical writing device 600 can be used as a constituent member of an image forming apparatus having a printer function using laser light.
Also, by making the scanning optical system different so that optical scanning is possible not only in one axis direction but also in two axis directions, a laser label device that performs printing by deflecting laser light to a thermal medium, optical scanning, and heating. It can be used as a component of the image forming apparatus.
The optical deflector 13 having the reflecting member 14 applied to the optical writing device 600 consumes less power for driving than a rotary polygon mirror using a polygon mirror or the like, and power saving of the optical writing device 600 is achieved. Is advantageous.
Further, since the wind noise during vibration of the optical deflector 13 is smaller than that of the rotary polygon mirror, it is advantageous for improving the quietness of the optical writing device 600. The optical writing device 600 requires much less installation space than the rotary polygon mirror, and the optical deflector 13 generates only a small amount of heat, so that it can be easily downsized. Therefore, it is advantageous for downsizing the image forming apparatus. Is

[Object recognition device]
Next, an object recognition device to which the drive device of the present embodiment is applied will be described in detail with reference to FIGS. 9 and 10.
FIG. 9 is a schematic diagram of an automobile equipped with a laser radar device which is an example of an object recognition device. FIG. 10 is a schematic diagram of an example of a laser radar device. The object recognition device is a device that recognizes an object in the target direction, for example, a laser radar device.

As shown in FIG. 9, a laser radar device 700 is mounted on, for example, an automobile 701, and recognizes the object 702 by receiving the reflected light from the object 702 existing in the object direction by optically scanning the object direction. To do.
As shown in FIG. 10, the laser light emitted from the light source device 12 passes through an incident optical system composed of a collimating lens 703 and a plane mirror 704, which is an optical system that makes diverging light substantially parallel, and is reflected by a reflecting member. The optical deflector 13 having 14 is scanned in the direction of one axis or two axes.
Then, the object 702 in front of the apparatus is irradiated through a projection lens 705 or the like that is a projection optical system. Driving of the light source device 12 and the optical deflector 13 is controlled by the driving device 11. The reflected light reflected by the object 702 is detected by the photodetector 709.
That is, the reflected light is received by the image sensor 707 via the condenser lens 706 that is a light receiving optical system, and the image sensor 707 outputs a detection signal to the signal processing circuit 708. The signal processing circuit 708 performs predetermined processing such as binarization and noise processing on the input detection signal, and outputs the result to the distance measurement circuit 710.

The distance measuring circuit 710 detects the object 702 based on the time difference between the timing at which the light source device 12 emits the laser light and the timing at which the light detector 709 receives the laser light, or the phase difference for each pixel of the received image sensor 707. The presence / absence is recognized, and further distance information with respect to the object 702 is calculated.
Since the optical deflector 13 having the reflecting member 14 is smaller and harder to break than the rotary polygon mirror, a highly durable small radar device can be provided.
Such a laser radar device is attached to, for example, a vehicle, an aircraft, a ship, a robot, and the like, and can optically scan a predetermined range to recognize the presence of an obstacle and the distance to the obstacle.

In the above object recognition apparatus, the laser radar apparatus 700 as an example has been described. However, the object recognition apparatus performs optical scanning by controlling the optical deflector 13 having the reflecting member 14 with the driving device 11, thereby detecting the light detector. Any device that recognizes the object 702 by receiving reflected light by 709 may be used, and the present invention is not limited to the above-described embodiment.
For example, biometric authentication that recognizes an object by calculating object information such as a shape from distance information obtained by optically scanning a hand or a face and referring to the record, or recognizes an intruder by optical scanning of an object range. The present invention can be similarly applied to a security sensor, a component member of a three-dimensional scanner that calculates and recognizes object information such as a shape from distance information obtained by optical scanning, and outputs it as three-dimensional data.

[Packaging]
Next, the packaging of the optical deflector controlled by the drive device of this embodiment will be described with reference to FIG.
FIG. 11 is a schematic diagram of an example of a packaged optical deflector.
As shown in FIG. 11, the optical deflector 13 is attached to an attachment member 801 disposed inside a package member 802 serving as a casing, and a part of the package member 802 is covered with a transmission member 803 and sealed. Packaged with.
Further, an inert gas such as nitrogen is sealed in the package. As a result, deterioration of the optical deflector 13 due to oxidation is suppressed, and durability against changes in the environment such as temperature is improved.
Next, details of the optical deflector used in the above-described optical deflection system, optical scanning system, image projection apparatus, optical writing apparatus, and object recognition apparatus and details of control by the driving apparatus of the present embodiment will be described.

[Details of optical deflector]
First, the optical deflector will be described in detail with reference to FIG.
FIG. 12 is a plan view of an optical deflector that can deflect light in two axial directions, ie, an X direction that is a main scanning direction and a Y direction that is a sub scanning direction. 13 is a sectional view taken along the line PP in FIG. 12, and FIG. 14 is a sectional view taken along the line QQ in FIG.
In the following description, the direction in which the light beam L reflected by the reflecting member 14 moves when the reflecting member 14 constituting the reflecting surface is driven around the first axis O1, as will be described later, is the main scanning direction. Is the direction in which the light beam L moves when driven around the second axis O2. In addition, it is not limited to such a structure, You may change suitably the main scanning direction and a subscanning direction according to a structure.

The optical deflector 13 includes a mirror unit 101 having a reflecting member 14 that reflects incident light L, and a first drive unit that is connected to the mirror unit 101 and drives the mirror unit 101 around a first axis O1 parallel to the Y axis. 110a, 110b.
The optical deflector 13 also has a first support part 120 as a support frame that supports the mirror part 101 and the first drive parts 110a and 110b.
The optical deflector 13 is also connected to the first support part 120 and drives the mirror part 101 and the first support part 120 around a second axis O2 parallel to the X axis, and a second drive. And a second support part 140 that supports the parts 130a and 130b.

In addition, the 1st drive part 110a, 110b, the mirror part 101, and the 1st support part 120 in this embodiment comprise the movable part rotated centering on the 2nd axis | shaft O2. The second driving units 130 a and 130 b support the movable unit with respect to the second support unit 140.
The optical deflector 13 includes first driving units 110a and 110b, second driving units 130a and 130b, and an electrode connection unit 150 that is electrically connected to the driving device.

  The optical deflector 13 is formed, for example, by forming a single SOI (Silicon On Insulator) substrate by an etching process or the like, and a first drive beam as a drive beam constituting the reflecting member 14 and the first drive units 110a and 110b on the formed substrate. The piezoelectric drive units 112a and 112b, the second drive units 131a to 131f and 132a to 132f constituting the second drive units 130a and 130b, the electrode connection unit 150, and the like are integrally formed. Note that each of the above-described components may be formed after the SOI substrate is formed or during the formation of the SOI substrate.

As shown in FIGS. 13 and 14, the SOI substrate includes a silicon support layer 161, which is a first silicon layer made of, for example, single crystal silicon (Si), and a silicon oxide layer 162 formed on the silicon support layer 161. And a silicon active layer 163 which is a second silicon layer formed on the silicon oxide layer 162.
Since the silicon active layer 163 has a small thickness in the Z-axis direction with respect to the X-axis direction or the Y-axis direction, the member formed of the silicon active layer 163 has a function as an elastic part having elasticity. In this embodiment, as shown in each drawing, the second driving units 130a and 130b and the first driving units 110a and 110b all have a silicon active layer 163 as a base material and have a function as an elastic portion. ing.
Note that the SOI substrate does not necessarily need to be planar, and may have a curvature or the like. Further, the member used for forming the optical deflector 13 is not limited to the SOI substrate as long as the substrate can be integrally formed by etching or the like and can be partially elastic.

The mirror unit 101 includes a mirror unit base 102 made of, for example, a circular plate member, and a reflecting member 14 formed on the surface of the mirror unit base 102 on the + Z side. The mirror unit 101 will be described later.
The first drive units 110a and 110b have two torsion bars 111a and 111b connected at one end to the mirror unit base 102 and extending in the first axis O1 direction to support the mirror unit 101 so as to be displaceable, and one end at the torsion bar 111a. , 111b and the other ends of the first piezoelectric drive portions 112a, 112b connected to the inner peripheral portion of the first support portion 120.

As shown in FIG. 13, the torsion bars 111 a and 111 b are configured using a silicon active layer 163. The first piezoelectric driving units 112a and 112b are configured by forming the lower electrode 201, the piezoelectric unit 202, and the upper electrode 203 in this order on the surface of the silicon active layer 163 on the + Z side.
The upper electrode 203 and the lower electrode 201 are configured using, for example, gold (Au) or platinum (Pt). The piezoelectric unit 202 is configured using, for example, PZT (lead zirconate titanate) which is a piezoelectric material.
The first support 120 is a rectangular support that is configured using the silicon support layer 161, the silicon oxide layer 162, and the silicon active layer 163 and is formed so as to surround the mirror unit 101. In order to avoid electrical connection with the lower electrode, an insulating layer made of, for example, a silicon oxide layer may be provided on the silicon active layer 163.

The second driving units 130a and 130b include a plurality of second piezoelectric driving units 131a to 131f and 132a to 132f that are connected in a folded manner, the second piezoelectric driving units 131a to 131f, and the second piezoelectric driving units 132a to 132f. It has the folding | returning part 205 which connects 132f. The second drive units 130a and 130b have a function as a meandering beam portion by connecting this configuration, that is, a plurality of piezoelectric drive units at the turn-back portion.
One end of each of the second driving units 130 a and 130 b is connected to the outer peripheral part of the first support part 120, and the other end is connected to the inner peripheral part of the second support part 140. At this time, the connection location between the second drive unit 130a and the first support unit 120, the connection location between the second drive unit 130b and the first support unit 120, and the connection between the second drive unit 130a and the second support unit 140 are also provided. It is desirable that the location and the location where the second drive unit 130 b and the second support unit 140 are connected are point-symmetric with respect to the center of the reflecting member 14.

  As shown in FIG. 14, the second piezoelectric driving units 130 a and 130 b are configured by forming a lower electrode 201, a piezoelectric unit 202, and an upper electrode 203 in this order on the surface of the silicon active layer 163 on the + Z side. The upper electrode 203 and the lower electrode 201 are configured using, for example, gold (Au) or platinum (Pt). The piezoelectric portion 202 is a piezoelectric member using, for example, PZT (lead zirconate titanate) which is a piezoelectric material.

  The second support unit 140 includes, for example, a silicon support layer 161, a silicon oxide layer 162, and a silicon active layer 163, and includes a mirror unit 101, first drive units 110a and 110b, a first support unit 120, and a second drive unit. It is a rectangular support formed so as to surround 130a and 130b.

The electrode connection part 150 is formed, for example, on the surface on the + Z side of the second support part 140, and each upper electrode 203 and each of the first piezoelectric drive parts 112a and 112b, the second piezoelectric drive parts 131a to 131f, and 132a to 132f. The lower electrode 201 and the driving device 11 shown in FIG. 1 are electrically connected via an electrode wiring such as aluminum.
Note that the upper electrode 203 and the lower electrode 201 may be directly connected to the electrode connecting portion 150, or may be indirectly connected by connecting the electrodes together.

  As shown in FIG. 14, the second piezoelectric drive units 131 a to 131 f are applied to the upper electrode 203, the lower electrode 201, the upper electrode 203, and the lower electrode 201, which are a pair of electrodes that apply a voltage and cause bending. It has a sandwiched piezoelectric portion 202 and a silicon active layer 163. The second piezoelectric driving units 132a to 132f are configured in the same manner.

Next, the mirror part 101 of the optical deflector 13 which is a characteristic part of the present invention will be described.
15A shows a mirror unit 101A used in a conventional optical deflector, and FIG. 15B shows a mirror unit 101 used in the optical deflector 13 of the present invention. Is a double-sided light deflection mirror that can be swung in a predetermined axial direction.
The mirror parts 101A and 101 are composed of, for example, disk-shaped mirror part bases 102A and 102, and reflecting members 14A and 14 that are provided on the surface of the mirror part bases 102A and 102 on the + Z side and form a reflective surface. The The mirror unit bases 102A and 102 are configured using, for example, a silicon active layer 163.

The reflecting members 14A and 14 are made of a metal thin film containing, for example, aluminum, gold, silver, or the like. Further, the mirror portions 101A and 101 may be provided with ribs for reinforcing the mirror portion on the surface of the mirror portion bases 102A and 102 on the −Z side.
The rib is configured using, for example, a silicon support layer 161 and a silicon oxide layer 162, and can suppress distortion of the reflecting members 14A and 14 caused by displacement of the mirror portions 101A and 101.

  The conventional optical deflector and the optical deflector 13 of the present invention are fixedly supported in such a manner that one end is connected to the mirror base bodies 102A and 102 and extends in the direction of the first axis O1 so as to sandwich the mirror parts 101A and 101. It has width torsion bars 111aA, 111bA, 111a, 111b. With this configuration, for example, when the vibration frequency of the torsion bars 111aA, 111bA, 111a, and 111b is set to about 20 kHz, which is about the same as the resonance frequency, mechanical resonance due to torsion of the torsion bars 111aA, 111bA, 111a, and 111b occurs. , The mirror portions 101A and 101 can be resonantly oscillated at about 20 kHz.

In the conventional optical deflector, the torsion bars 111aA and 111bA are formed to have the same width, but in the optical deflector 13 of the present invention, the width of the torsion bars 111a and 111b gradually decreases as the distance from the mirror unit 101 increases. Tapered regions 103a and 103b are formed at one end of each.
Further, in the conventional optical deflector, the reflecting member 14A is circular, whereas the reflecting member 14 included in the optical deflector 13 of the present invention includes a circular main body portion 14c and each tapered region 103a, Projection portions 14a and 14b are formed so as to project in the 103b direction, that is, in the first axis O1 direction, which is a displaceable axis of the mirror portion 101.

16A shows an AA section in FIG. 15B, and FIG. 16B shows a BB section in FIG. 15B. As shown in FIG. 16A, the mirror base 102 is mainly composed of a silicon active layer 163 that is an elastic member.
The mirror base 102 may be constituted by a silicon support layer 161 and a silicon oxide layer 162 instead of the silicon active layer 163. The silicon active layer 163 may be formed by etching the SOI substrate.

The reflection member 14 includes a reflection film 41 that plays a role of reflecting light and an interlayer film 42. The interlayer film 42 is used in the manufacturing process or for the purpose of increasing the adhesion between the layers. The reflective member 14 is formed by laminating the interlayer film 42 and the reflective film 41 in this order in the + Z direction of the silicon active layer 163.
The interlayer film 42 is made of, for example, silicon oxide, and the reflective film 41 is made of, for example, a metal thin film containing aluminum, gold, silver, or the like. The outer peripheral edge of the mirror base 102 and the outer peripheral edge of the reflecting member 14 are each formed to have a predetermined width 43 that is a distance of 0 or more in a manufacturing process such as an etching process.
With this configuration, it is possible to increase the processing accuracy while keeping the etching width constant, and also prevent the reflecting member 14 from protruding outside the mirror portion base 102 and damaging the reflecting member 14 due to film peeling from the protruding portion. be able to.

  FIG. 17A is a schematic diagram when the mirror unit 101A having the reflecting member 14A and the torsion bars 111aA and 111bA are resonantly oscillated, and FIG. 17B shows the mirror unit 101A and the torsion bar 111aA at that time. The enlarged view in the connection part of each is shown. When a vibration component substantially equal to the resonance frequency inherent to the machine is given, the mirror portion 101A swings around the first axis O1 supported by the torsion bars 111aA and 111bA. At this time, stress concentration due to torsion occurs at the connection portion between the mirror portion 101A and the torsion bars 111aA and 111bA, and the stress concentration increases as the angle becomes sharper and causes the silicon active layer 163 to break.

Since the reflective film and the interlayer film that constitute the reflective member 14A are laminated in the + Z direction of the silicon active layer that constitutes the mirror part 101A, there is a risk that film peeling will occur where the reflective film and the interlayer film are peeled off due to increased strain.
Further, when the tangent line in the second axis O2 direction at the connecting portion between the mirror part 101A and the torsion bars 111aA and 111bA is equal to the tangent line in the second axis O2 direction at the end point in the first axis O1 direction of the reflecting member 14A The reflective film and the interlayer film may peel off starting from the end point in the first axis O1 direction of the reflective member 14A.

Therefore, in the present invention, as shown in FIG. 15B, the torsion bars 111a and 111b have the tapered regions 103a and 103b to suppress stress concentration, and the reflective film 41 and the interlayer film 42 of the reflective member 14 are peeled off. To prevent that. The first axis O1 direction, which is the rotation axis of the mirror part 101, is less affected by the rotational moment. By providing the projecting parts 14a and 14b that are enlarged in this direction, the reflection film 41 and the interlayer film 42 of the reflection member 14 are formed. Prevents peeling.
Further, since the reflecting member 14 has the tapered regions 103a and 103b, that is, the projecting portions 14a and 14b formed so as to project in the first axis O1 direction, the area of the reflecting member 14 is enlarged and the film adhesion to the silicon active layer 163 is increased. The reflection film 41 and the interlayer film 42 of the reflection member 14 are prevented from being peeled off.
Further, the reflection film 41 and the interlayer film 42 are prevented from peeling off from the end points by separating the end points of the reflection member 14 in the first axis O1 direction from the stress concentration locations. Furthermore, the reflection efficiency of the irradiated light is improved by increasing the area of the reflecting member 14, and at the same time, the occurrence of beam diameter distortion due to the fact that the light is not reflected can be reduced.

Stress concentration due to torsion between the mirror portion 101 and the torsion bars 111a and 111b is more strongly generated in the acute angle portion. In the optical deflector 13 of the present invention, as shown in FIG. 18, since the connecting portions of the mirror portion 101, the torsion bars 111a and 111b, and the tapered regions 103a and 103b are respectively formed in curves, the stress concentration is suppressed. The reflection film 41 and the interlayer film 42 of the reflection member 14 are prevented from peeling off.
Further, the reflection member 14 is formed in a curved connection so that an acute angle portion is not formed at the connection portion between the main body portion 14c and the projecting portions 14a and 14b. With this configuration, it is possible to reduce the occurrence of breakage of the torsion bars 111a and 111b and the peeling of the reflecting film 41 and the interlayer film 42 of the reflecting member 14 that occur when the optical deflector 13 is caused to resonate and continue high-quality optical scanning. Thus, the optical deflector 13 that can be realized can be provided.

In the present embodiment, the case where the piezoelectric portion 202 is formed only on one surface (+ Z side surface) of the silicon active layer 163 that is an elastic portion has been described as an example. For example, it may be provided on the surface on the −Z side), or may be provided on both one surface and the other surface of the elastic portion.
In addition, the shape of each component is not limited to the shape of the embodiment as long as the mirror unit 101 can be displaced about the first axis O1 or the second axis O2. For example, the torsion bars 111a and 111b and the first piezoelectric drive units 112a and 112b may have a curved shape.

Also, on the + Z side surface of the upper electrode 203 of the first driving unit 110a, 110b, on the + Z side surface of the first support unit 120, on the + Z side surface of the upper electrode 203 of the second driving unit 130a, 130b, An insulating layer made of a silicon oxide film may be formed on at least one of the surfaces on the + Z side of the second support part 140.
At this time, an electrode wiring is provided on the insulating layer, and the insulating layer is partially removed or not formed as an opening at a connection spot where the upper electrode 203 or the lower electrode 201 and the electrode wiring are connected. The degree of freedom in designing the first driving units 110a and 110b, the second driving units 130a and 130b, and the electrode wiring can be increased, and a short circuit due to contact between the electrodes can be suppressed. The insulating layer may be any member having an insulating property, and may have a function as an antireflection member.

[Details of control of drive unit]
Next, details of control of the driving device 11 that drives the first driving units 110a and 110b and the second driving units 130a and 130b, which are movable devices, will be described.
When the positive or negative voltage is applied in the polarization direction, the piezoelectric unit 202 included in the first driving unit 110a and 110b and the second driving unit 130a and 130b is deformed (for example, expansion and contraction) in proportion to the potential of the applied voltage. The so-called reverse piezoelectric effect is exhibited. The first driving units 110a and 110b and the second driving units 130a and 130b displace the mirror unit 101 using the above-described inverse piezoelectric effect.
At this time, the angle at which the light beam incident on the reflecting member 14 is deflected is called a deflection angle. The deflection angle when no voltage is applied to the piezoelectric portion 202 is zero, and the deflection angle larger than that angle is defined as a positive deflection angle, and the deflection angle is defined as a negative deflection angle.

First, control of the drive device 11 that drives the first drive units 110a and 110b will be described.
In the first driving units 110a and 110b, when a driving voltage is applied in parallel to the piezoelectric unit 202 included in the first piezoelectric driving units 112a and 112b via the upper electrode 203 and the lower electrode 201, the respective piezoelectric units 202 are deformed. To do. Due to the action of the deformation of the piezoelectric portion 202, the first piezoelectric driving portions 112a and 112b are bent and deformed. As a result, the driving force around the first axis O1 acts on the mirror portion 101 via the twist of the two torsion bars 111a and 111b, and the mirror portion 101 is displaced around the first axis O1. The driving voltage applied to the first driving units 110 a and 110 b is controlled by the driving device 11.

Therefore, the drive unit 11 applies the drive voltage having a predetermined sine waveform in parallel to the first piezoelectric drive units 112a and 112b included in the first drive units 110a and 110b, so that the mirror unit 101 is moved around the first axis O1. It can be displaced at a cycle of a driving voltage having a predetermined sine waveform.
In particular, for example, when the frequency of the sinusoidal waveform voltage is set to about 20 kHz, which is approximately the same as the resonance frequency of the torsion bars 111a and 111b, the mechanical resonance due to the torsion of the torsion bars 111a and 111b occurs. The part 101 can be resonantly oscillated at about 20 kHz.

Next, control of the drive device 11 that drives the second drive units 130a and 130b will be described.
FIG. 19 is a schematic diagram schematically illustrating driving of the second drive units 130a and 130b of the optical deflector. A region represented by diagonal lines is the mirror unit 101 or the like.
Among the plurality of second piezoelectric drive units 131a to 131f included in the second drive unit 130a, the even-numbered second piezoelectric drive units counted from the second piezoelectric drive unit (131a) closest to the mirror unit 101, that is, the first The two piezoelectric drive units 131b, 131d, and 131f are referred to as a piezoelectric drive unit group A.
In addition, among the plurality of second piezoelectric drive units 132a to 132f included in the second drive unit 130b, odd-numbered second piezoelectric drive units counted from the second piezoelectric drive unit (132a) closest to the mirror unit 101, That is, the second piezoelectric drive units 132a, 132c, and 132e are similarly referred to as a piezoelectric drive unit group A. When the drive voltages are applied in parallel to the piezoelectric drive unit group A, the mirror unit 101 is bent around the second axis O2 so as to bend and deform in the same direction as shown in FIG. It is movable.

Of the plurality of second piezoelectric drive units 131a to 131f of the second drive unit 130a, the odd-numbered second piezoelectric drive units counted from the second piezoelectric drive unit (131a) closest to the mirror unit, that is, The second piezoelectric drive units 131a, 131c, and 131e are referred to as a piezoelectric drive unit group B.
In addition, among the plurality of second piezoelectric drive units 132a to 132f included in the second drive unit 130b, the even-numbered second piezoelectric drive units counted from the second piezoelectric drive unit (132a) closest to the mirror unit, that is, Similarly, let 132b, 132d, and 132f be the piezoelectric drive unit group B. When the driving voltage is applied in parallel to the piezoelectric driving unit group B, the piezoelectric driving unit group B bends and deforms in the same direction, and the mirror unit 101 has a negative deflection angle as shown in FIG. 19C. It moves around the second axis O2.

As shown in FIGS. 19A and 19C, the second drive units 130a and 130b bend the plurality of piezoelectric units 202 included in the piezoelectric drive unit group A or the plurality of piezoelectric units 202 included in the piezoelectric drive unit group B. By deforming, the amount of movement due to bending deformation can be accumulated, and the deflection angle around the second axis O2 of the mirror unit 101 can be increased.
As shown in FIG. 12, the second driving units 130 a and 130 b are connected so as to be point-symmetric with respect to the first support unit 120 around the center point of the first support unit 120. Therefore, when a driving voltage is applied to the piezoelectric driving unit group A, the second driving unit 130a generates a driving force for moving the first supporting unit 120 in the + Z direction at the connection portion with the first supporting unit 120, and the second driving unit 130b A driving force for moving the first support unit 120 in the −Z direction is generated at the connection portion with the first support unit 120, and the movable amount is accumulated, so that the deflection angle around the second axis O2 of the mirror unit 101 can be increased. .

Further, as shown in FIG. 19B, the movable amount of the mirror unit 101 by the piezoelectric drive unit group A when no voltage is applied or by voltage application, and the movable amount of the mirror unit 101 by the piezoelectric drive group B by voltage application When is balanced, the deflection angle is zero.
The mirror unit 101 is driven around the second axis O2 by applying a driving voltage to the second piezoelectric driving units 131a to 131f and 132a to 132f so as to continuously repeat FIGS. 19 (a) to 19 (c). Can be made.

[Drive voltage]
The drive voltage applied to the second drive unit is controlled by the drive device 11.
With reference to FIG. 20, the drive voltage applied to the piezoelectric drive unit group A (hereinafter referred to as drive voltage A) and the drive voltage applied to the piezoelectric drive unit group B (hereinafter referred to as drive voltage B) will be described. In addition, an application unit that applies the drive voltage A (first drive voltage) is a first application unit, and an application unit that applies the drive voltage B (second drive voltage) is a second application unit.

  20A shows an example of the waveform of the drive voltage A applied to the piezoelectric drive unit group A of the optical deflector 13, and FIG. 20B shows the drive applied to the piezoelectric drive unit group B of the optical deflector 13. An example of the waveform of the voltage B is shown in FIG. 20C, in which the waveform of the drive voltage A and the waveform of the drive voltage B are superimposed.

As shown in FIG. 20A, the waveform of the drive voltage A is, for example, a sawtooth waveform, and the frequency is, for example, 60 Hz.
Further, the waveform of the drive voltage A has a rising time period TrA in which the voltage value increases from the minimum value to the next maximum value, and a falling period in which the voltage value decreases from the maximum value to the next minimum value. For example, a ratio of TrA: TfA = 9: 1 is set in advance, where TfA is TfA. At this time, the ratio of TrA to one cycle is referred to as symmetry of drive voltage A.

As shown in FIG. 20B, the waveform of the drive voltage B is, for example, a sawtooth waveform, and the frequency is, for example, 60 Hz.
In addition, the waveform of the drive voltage B indicates that the time width of the rising period in which the voltage value increases from the minimum value to the next maximum value is TrB, and the falling period in which the voltage value decreases from the maximum value to the next minimum value. For example, a ratio of TfB: TrB = 9: 1 is set in advance. At this time, the ratio of TfB to one cycle is called symmetry of the drive voltage B.
Further, as shown in FIG. 20C, for example, the period TA of the waveform of the drive voltage A and the period TB of the waveform of the drive voltage B are set to be the same.

The sawtooth waveform of the driving voltage A and the driving voltage B described above is generated, for example, by superimposing sine waves.
In the present embodiment, the drive voltages A and B use a sawtooth waveform drive voltage. However, the present invention is not limited to this, and a drive voltage having a sawtooth waveform rounded or a sawtooth waveform straight line. It is also possible to change the waveform according to the device characteristics of the optical deflector 13, such as a drive voltage having a waveform with a curved region. The symmetry in this case is the ratio of the rise time to one cycle or the ratio of the fall time to one cycle. At this time, it may be arbitrarily set whether the rise time or the fall time is used as a reference.

FIG. 21 shows the mirror unit 104 used in the second embodiment of the present invention. Compared with the mirror unit 101 described above, this mirror unit 104 is different only in that it has a reflecting member 16 that constitutes a reflecting surface instead of the reflecting member 14, and the other configuration is the same.
As shown in FIG. 21A, the reflecting member 16 has a circular main body portion 16c, and a first axis O1 that is a displaceable axis of the mirror portion 104 in the directions of the tapered regions 103a and 103b from the main body portion 16c. And projecting portions 16a and 16b that project in the direction.
Further, as shown in FIG. 21B, the reflecting member 16 is configured by laminating a reflecting film 41 on the upper surface of the interlayer film 42, similarly to the reflecting member 14.

In each of the protrusions 16a and 16b, a plurality of dividing holes 44 formed by partially cutting the interlayer film 42 when the protrusions 16a and 16b are formed are formed at predetermined intervals. Yes. Each dividing hole 44 is formed in such a manner that the reflective film 41 is stamped on the silicon active layer 163, but the number and size of the formed dividing holes 44 are not limited.
With this configuration, the degree of adhesion between the silicon active layer 163 and the reflective film 41 can be improved, and the reflective member 16 that is less likely to peel off than the reflective member 14 can be provided.
Similar effects can be obtained by forming the groove-shaped dividing groove 45 shown in FIG. 21C instead of the hole-shaped dividing hole 44.

FIG. 22 shows the mirror unit 105 used in the third embodiment of the present invention. This mirror unit 105 is different from the above-described mirror unit 101 only in that it has a reflecting member 17 that constitutes a reflecting surface in place of the reflecting member 14 and that a mirror unit base 50 is used in place of the mirror base 102. The other configurations are the same.
The mirror base 50 has an elliptical outer shape, and is connected to each of the torsion bars 111a and 111b in a curved manner in the respective tapered regions 103a and 103b.
The reflecting member 17 includes an oval body portion 17c and a projecting portion 17a that projects from the body portion 17c in the direction of the tapered regions 103a and 103b, that is, in the direction of the first axis O1 that is the axis of the mirror portion 105 that can be displaced. , 17b.
With this configuration, since the influence of film peeling due to the influence of the rotational moment is small in the axial direction, it is possible to provide a mirror portion that can enlarge the reflection region while suppressing film peeling.

FIG. 23 shows a mirror unit 106 used in the fourth embodiment of the present invention. Compared with the mirror part 101 described above, the mirror part 106 is only in a point where the center line S0 in the first axis O1 direction of the mirror part base body 102 and the center line S1 in the same direction of the reflecting member 14 are shifted. They are different and the other configurations are the same.
With this configuration, the amount of rotation of the reflecting member 14 can be increased as compared to the mirror unit 101. In the above configuration, the displacement center line of the mirror unit 106 is S0, but the displacement center line of the mirror unit 106 may be S1.

  In each of the above-described embodiments, the optical deflector 13 shown in FIG. 12 is shown as an optical deflector to which each mirror unit 101, 104, 105, 106 can be applied. The optical deflector 13 has a so-called cantilever structure in which the first piezoelectric drive units 112a and 112b, which are drive beams, are provided only on the + X side with the first axis O1 as the center. However, the optical deflector to which the present invention can be applied is not limited to this. For example, as shown in FIG. 24, in addition to the first piezoelectric driving units 112a and 112b, they are provided at positions targeting the first axis O1. The present invention can also be applied to the so-called dual-supported optical deflector 19 having the first piezoelectric driving portions 112c and 112d.

  In the embodiment described above, the same driving method is adopted for the driving means for displacing the movable part in the main scanning direction (movable part) and the driving means for displacing the movable part in the sub-scanning direction (second movable part). However, these may employ different driving methods. Also, the driving method is not limited to the piezoelectric driving method using a piezoelectric element, and for example, an electrostatic driving method that uses electrostatic force or an electromagnetic driving method that uses electromagnetic force may be adopted. Good.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to such specific embodiments, and unless specifically limited by the above description, the present invention described in the claims is not limited. Various modifications and changes are possible within the scope of the gist. The effects described in the embodiments of the present invention are merely examples of the most preferable effects resulting from the present invention, and the effects of the present invention are limited to those described in the embodiments of the present invention. is not.

10 Optical scanning device (optical scanning system)
DESCRIPTION OF SYMBOLS 12 Light source device 13, 19 Optical deflector 14, 16, 17 Reflective member 14a, 14b, 16a, 16b, 17a, 17b Protrusion part 14c, 16c, 17c Body part 43 Predetermined width 101, 104, 105, 106 Mirror part 103a , 103b Tapered regions 111a, 111b Torsion bars 112a, 112b Driving beam (first piezoelectric driving unit)
120 Support frame (first support part)
500 Image projection device (head-up display device)
501R, 501G, 501B Laser light source 507 Combining means (light quantity adjustment unit)
700 Object recognition device (laser radar device)
710 Distance measuring circuit

JP, 2006-40633, A

Claims (10)

A mirror part having a reflecting member that reflects light and being displaceable about an axis;
A pair of torsion bars having one end connected to the mirror portion and supporting the mirror portion;
A pair of drive beams connected to the other end of the torsion bar and supporting the torsion bar in a displaceable manner;
A support frame to which each drive beam is connected;
The reflecting member has a main body portion and a protruding portion that protrudes from the main body portion in the axial direction. The optical deflector according to claim 1.
The optical deflector according to claim 1, wherein the reflecting member is formed so that an outer peripheral edge thereof is located inside with a predetermined width from an outer peripheral edge of the mirror portion. The optical deflector according to claim 1 or 2,
The mirror part and the body part are both circular, and the projecting part is connected to the body part in a curved manner. The optical deflector according to claim 1 or 2,
Both the mirror part and the main body part have an elliptical shape having a major axis in the axial direction, and the projecting part is connected to the main body part in a curved manner. The optical deflector according to any one of claims 1 to 4,
Each of the torsion bars has a tapered region formed at each end so that the width gradually decreases as the distance from the mirror portion increases, and the protruding portion is formed on the tapered region. Deflector. The optical deflector according to claim 5, wherein
The optical deflector characterized in that the main body part, the projecting part or the tapered region has an asymmetric part asymmetric with respect to the axis. An optical scanning device comprising the optical deflector according to any one of claims 1 to 6,
An optical scanning apparatus comprising: a light source that emits light; and an irradiation unit that irradiates the light emitted from the light source and deflected by the optical deflector in a predetermined direction. An image projection apparatus comprising the optical scanning device according to claim 7,
An image projection apparatus, wherein the light deflector deflects and projects the light. The image projector according to claim 8.
A plurality of light sources, and a combining unit that combines a plurality of lights emitted from the respective light sources, and the optical deflector deflects and projects each of the lights combined by the combining unit. A characteristic image projection apparatus. An object recognition device comprising the optical deflector according to any one of claims 1 to 6,
An object recognition apparatus comprising: a light source that emits light; and a distance measuring circuit that calculates a presence / absence of an object and a distance from the object.

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