JP6648443B2 - Optical deflector, two-dimensional image display device, optical scanning device, and image forming device - Google Patents

Description

  The present invention relates to an optical deflector, a two-dimensional image display device, an optical scanning device, and an image forming device.

In recent years, as a means for deflecting and scanning a light beam, a small-sized optical deflector based on micromachining technology using semiconductor manufacturing technology has been developed.
This type of optical deflector is formed by integrally forming a movable portion having a light reflecting surface on a substrate and a driving beam for vibrating the movable portion by a micromachining technique for finely processing silicon or glass.
The drive beam is formed by superposing a piezoelectric body made of a thinned piezoelectric material on the surface of the cantilever, and the piezoelectric body functions as an actuator.
In-plane expansion and contraction caused by the piezoelectric characteristics of the piezoelectric body are transmitted to the cantilever, and the cantilever can be vibrated.
The light reflecting surface is rotated and vibrated by the vibration of the cantilever, and the light can be deflected.

In the configuration for performing two-dimensional scanning, resonance driving is used for optical scanning in the horizontal direction.
Raster scanning is required to achieve high definition and uniformity in a display image, and non-resonant driving is generally used for optical scanning in the vertical direction.

  Patent Literature 1 discloses that an optical deflector that performs two-dimensional scanning adjusts a phase difference between a sawtooth wave applied as a driving voltage in a one-axis scanning direction and a driving voltage in a two-axis scanning direction orthogonal to the one-axis scanning direction, thereby causing high-frequency vibration of a mirror unit. There is disclosed a technique for suppressing the occurrence of blemishes.

However, in driving for raster scanning in the vertical direction, a driving force generated during raster scanning may affect the horizontal direction.
For this reason, a component that oscillates in the horizontal direction during raster scanning in the vertical direction is generated, and a phenomenon that the scanning line in the vertical direction fluctuates in terms of image quality.
This fluctuation of the scanning line causes a decrease in image quality.

  SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and has as its main object to provide an optical deflector capable of suppressing fluctuation of a scanning line and contributing to an improvement in image quality.

The invention according to claim 1 includes a mirror unit having a light reflecting surface, a movable frame including the mirror unit, a support frame supporting the movable frame, and the movable frame and the support frame on both sides of the movable frame. A meandering beam portion having a folded shape, one end of each of the meandering beam portions is fixed to the support frame, and the other end is connected to the movable frame at each connection portion. Each of the meandering beam portions is fixed and has a configuration that deforms by applying a voltage, and the deformation of each of the meandering beam portions due to voltage application is transmitted through the movable frame to thereby cause the mirror portion to move. Vibrates about a rotation axis, each of the meandering beam portions and each of the connection portions include at least a first silicon layer integrally formed, and each of the meandering beam portions includes the first silicon layer. First acid on top of silicon layer Has a piezoelectric member via the silicon layer, respectively, each connecting portion on the side opposite to the side where the piezoelectric member is disposed in the first silicon layer, through the second silicon oxide layer, A vibration suppression unit that includes a second silicon layer that suppresses a vibration component on a surface of the movable frame and a rotation axis perpendicular to the rotation axis when the mirror unit is not vibrating. And

  ADVANTAGE OF THE INVENTION According to this invention, the fluctuation | variation of a scanning line can be suppressed and the optical deflector which can contribute to image quality improvement can be implement | achieved.

FIG. 2 is a front view of the optical deflector according to the first embodiment of the present invention. It is a top view of a meandering beam part. It is a figure which shows the waveform of the voltage applied to a meandering beam part, (a) is a figure which shows the waveform with respect to a 1st meandering beam part, (b) is a figure which shows the waveform with respect to a 2nd meandering beam part. . It is a figure which shows the operation state of an optical deflector, (a) is a perspective view of a non-driving state, (b) is a side view which shows the deformation | transformation operation | movement of each beam part in a meandering beam part in a driving state. FIGS. 7A and 7B are image diagrams showing experimental results of scanning line fluctuation with and without a vibration suppressing unit, wherein FIG. 7A shows a state in which there is no vibration suppressing unit and scanning line fluctuation occurs, and FIG. FIG. 6 is a diagram illustrating a state in which scanning line fluctuation is suppressed. FIGS. 2A and 2B are cross-sectional views of a connection portion showing a vibration suppressing portion, wherein FIG. 1A is a cross-sectional view taken along line L-L ′ in FIG. 1 and FIG. 2B is a cross-sectional view taken along line L1-L1 ′. FIG. 9 is a characteristic diagram illustrating a relationship between a width of a vibration suppression unit and a scanning line fluctuation amount. FIGS. 7A and 7B are diagrams illustrating an arrangement state of connection portions, in which FIG. 7A is a schematic diagram illustrating a state in which the connection portions are arranged point-symmetrically with respect to the center of the movable frame, and FIG. FIG. It is a front view of the optical deflector according to the second embodiment. FIG. 3 is a diagram illustrating a relationship between biaxial scanning and vibration of the optical deflector. It is sectional drawing in the L-L 'line | wire of FIG. 1 which shows the modification of a vibration suppression part. It is a perspective view which shows the mounting structure of an optical deflector. FIG. 13 is a diagram illustrating a configuration of a projector as a two-dimensional image display device according to a third embodiment. It is a figure showing the composition of the head up display as a two-dimensional image display concerning a 3rd embodiment. It is a perspective view showing the optical scanning device concerning a 4th embodiment. FIG. 13 is a diagram illustrating an image forming apparatus according to a fifth embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The first embodiment will be described with reference to FIGS.
The optical deflector 2 is a one-axis scanning type optical deflector that can perform optical scanning in the vertical direction (Y direction).
The light deflector 2 includes a mirror portion 4 having a light reflecting surface, a flat movable frame 6 including the mirror portion 4, and a support frame 8 arranged to surround the outside of the movable frame 6. .
The optical deflector 2 includes a first meandering beam portion 10 disposed between the movable frame 6 and the support frame 8 on both sides of the movable frame 6 in the Y-axis direction, and a second meandering beam portion. Beam portion 12.

One end 10 a of the first meandering beam portion 10 is fixed to the support frame 8, and the other end 10 b is fixed to the movable frame 6.
A fixed portion between the other end 10b of the first meandering beam portion 10 and the movable frame 6 serves as a connection portion C1.
Similarly, one end 12 a of the second meandering beam portion 12 is fixed to the support frame 8, and the other end 12 b is fixed to the movable frame 6.
A fixed portion between the other end 12b of the second meandering beam portion 12 and the movable frame 6 serves as a connection portion C2.
As described above, the movable frame 6 is indirectly supported by the support frame 8 by the first meandering beam portion 10 and the second meandering beam portion 12.

As shown in FIG. 2, the first meandering beam portion 10 and the second meandering beam portion 12 have a folded shape in which elongated beam portions A and beam portions B are alternately located in the X direction. .
The piezoelectric members 14 are provided on the surfaces of the beam portions A and B except for the folded portions, so that the beam portions A and B can be driven independently.
When different voltages are applied to the piezoelectric members 14 of the beam portions A and B, the beam portions A and B warp (deform), respectively, and the adjacent beam portions bend in different directions.
The flexure is accumulated and transmitted to the movable frame 6, and non-resonant rotational vibration of the mirror unit 4 is generated around the X axis (= vertical direction), thereby having a scanning function as an optical deflector.
In FIG. 2, the mirror unit 4 is omitted.

The driving principle of the optical deflector 2 will be described with reference to FIGS.
For the plurality of piezoelectric members 14 provided on each of the meandering beam portions A and B of the first meandering beam portion 10 and the second meandering beam portion 12, the piezoelectric member 14 of the beam portion A includes: A sawtooth voltage shown in FIG. 3A is applied.
As shown in FIG. 3B, a sawtooth voltage having a shape opposite to that of FIG. 3A is applied to the piezoelectric member 14 of the beam portion B.

When a voltage having a different waveform is applied to the piezoelectric member 14 provided on each of the beam portions A and B, the first meandering beam portion 10 and the second meandering beam portion 12 operate as cantilevers, respectively, and are movable. The frame 6 rotates and vibrates.
In FIG. 3, reference characters Ta and Tb denote waveform periods, Ta1 and Tb2 denote voltage waveforms (saw waveforms) applied to the beam A, and Ta2 and Tb2 denote voltage waveforms (saw waveforms) applied to the beam B. I have.
FIG. 4A shows a non-operating state of the optical deflector 2, and FIG. 4B shows a change of the meandering beam portion in an operating state of the optical deflector 2.

With reference to FIG. 5, a description will be given of position fluctuation (scanning line fluctuation) generated when a laser is scanned by this type of optical deflector.
In the optical deflector provided with the meandering beam portion, when laser scanning is performed by rotating and oscillating the mirror portion by raster driving, the laser scanning line fluctuates perpendicularly to the scanning direction as shown in FIG. Will be.
The reason is that there is a slight difference between the driving force of the first meandering beam and the driving force of the second meandering beam due to a processing error in the manufacturing process of the optical deflector and a variation in the driving force of the piezoelectric member. is there.
It has also been found that the above-mentioned phenomenon is caused to occur greatly even when the structure in the movable frame becomes asymmetric.

  When an optical deflector that causes scanning line fluctuation is applied to an image display device, a problem arises in that the effect on high image quality is impaired.

In order to cope with the above problem, in the optical deflector 2 according to the present embodiment, as shown in FIG. 4 is provided with a vibration suppression unit that suppresses a vibration component in a direction orthogonal to the vibration direction.
More specifically, the vibration suppressing unit 16 is provided at the connecting portions C1 and C2 (see FIG. 1) between the first meandering beam portion 10 and the movable frame 6.
FIG. 6A is a cross-sectional view taken along line LL ′ of the connecting portion C1 in FIG. 1, and FIG. 6B is a cross-sectional view taken along line L1-L1 ′ of the connecting portion C1.

As shown in FIG. 6A, the piezoelectric member 14 disposed on the surface of the beam portion B in the connection portion C1 includes a lower electrode 18, a piezoelectric material 20, an upper electrode 22, an insulating layer 24 are stacked.
The beam portion B is integrally formed of the same material as the movable frame 6.
The vibration suppressing portion 16 is formed by bonding a substrate of the same material (member) as the substrate forming the beam portion B and the movable frame 6 and removing unnecessary portions.

In other words, the vibration suppressing unit 16 is formed by increasing the thickness of the substrate on the side opposite to the piezoelectric member 14. Similarly, the vibration suppressing portion 16 is formed in the connection portion C2 .
In FIG. 6B, reference numeral g denotes a space between the movable frame 6 and the beam B.

A method for manufacturing the optical deflector 2 will be specifically described.
An SOI (Silicon On Insulator) substrate is usually used as a substrate for forming the beam portion B as a first support layer for supporting the piezoelectric member 14 and the vibration suppressing portion 16 as a second support layer.
The SOI substrate includes silicon on the active layer side (second support layer), a buried oxide film layer, and silicon on the base layer side (first support layer).

A silicon oxide film is formed on the surface of the SOI substrate, and thereafter, a lower electrode material, a piezoelectric material, and an upper electrode material are sequentially formed.
Thereafter, the upper electrode material, the piezoelectric material, and the lower electrode material are patterned in different patterns.
At this time, each pattern is patterned in an arbitrary form according to the performance required of the optical deflector and the like, and the silicon oxide film is etched in the same pattern as the lower electrode material.

Generally, the lower electrode material is also used as a wiring material. Thereafter, an insulating film is formed, a connection hole is opened, and a lead wiring material is formed and patterned.
After that, an insulating film and a mirror film are formed. Thereafter, the active layer, the base layer, and the buried oxide film are sequentially patterned and etched to complete the optical deflector.

The material and thickness of each part in the present embodiment are as follows.
Insulating layer 24: SiO ₂ (silicon dioxide; thickness 0.7 μm)
Upper electrode 22: Pt (platinum; thickness 0.2 μm)
Piezoelectric material 20: PZT (lead zirconate titanate; thickness 2 μm)
Lower electrode 18: Ir (iridium; thickness 0.15 μm)
Beam part B: Si (silicon; thickness 40 μm)
Vibration suppressor 16: Si (silicon; thickness 40 μm, width W 200 μm)

In the measurement result of the laser scanning line by the optical deflector in the case where the vibration suppressing unit 16 is not provided at the connection part C1, as shown in FIG. 5A, the scanning line fluctuation occurs.
On the other hand, according to the measurement result of the laser scanning line by the optical deflector 2 having the vibration suppressing portions 16 formed at the connection portions C1 and C2, as shown in FIG. 5B, the fluctuation of the scanning line can be suppressed.
Measurement result of scanning line fluctuation during scanning in comparison between the case where the width W (see FIG. 6A) of the vibration suppressing unit 16 is half (100 μm) of the above embodiment and the case where no vibration suppressing unit 16 is provided. Is shown in FIG. The scanning line fluctuation amount is the ratio of the deviation of the scanning line from the straight line due to the mirror deflection and the total width of the scanning line in the linear direction approximated to the straight line. The smaller the value, the more the fluctuation of the scanning line is suppressed.
From FIG. 7, it can be seen that by optimizing the vibration suppressing unit 16, the fluctuation of the scanning line can be suppressed to a level that does not substantially affect the image quality.

In other words, even if there is a processing error or a variation in the driving force of the piezoelectric member in the manufacturing process of the optical deflector, the presence of the vibration suppressing unit 16 can suppress the imbalance due to these errors.
It can be said that this also contributes to increasing the degree of freedom in designing the manufacturing accuracy of the optical deflector.
In the present embodiment, the vibration suppressor 16 is provided at both of the connecting portions C1 and C2. However, when the processing error of the optical deflector and the variation of the driving force of the piezoelectric member are corrected, the vibration suppressing portion 16 is connected to the connecting portion C1. It may be provided in any one of the portions C2.
The range in which the vibration suppressing portion 16 is provided is a range in which the deformation operation of the beam portion of the meandering beam portion is not hindered.

Here, optimization of the vibration suppression unit by changing the width W has been described as an example, but vibration can also be suppressed by optimizing the weight by changing the material or the like without changing the width W. In this case, the suppression of vibration can be more strongly suppressed by increasing the weight.
A configuration in which the thickness (height) of the vibration suppressing portion is adjusted without changing the width W may be employed. In this case, the thickness may be partially increased. For example, the thickness may be relatively increased as approaching the mirror section.

In addition, in the optical deflector 2 of the present embodiment, as shown in FIG. 8A, a connection portion C1 between the first meandering beam portion 10 and the movable frame 6, a second meandering beam portion 12, The connection portion C2 with the movable frame 6 is arranged point-symmetrically with respect to the center 6a of the movable frame 6.
As shown in FIG. 8B, when the connecting portions C1 and C2 are not arranged point-symmetrically with respect to the center 6a of the movable frame 6, the first meandering beam portion 10 and the second meandering beam portion are provided. Twelve driving force differences occur, and the amount of torsional displacement in the Y-axis direction that causes scanning line fluctuations increases.
In other words, the drive balance on both sides of the movable frame 6 is lost, and an unexpected twist mode occurs, which causes a scanning line fluctuation.
By disposing the connecting portions C1 and C2 in point symmetry with respect to the center 6a of the movable frame 6, it is possible to suppress scanning line fluctuation with high accuracy.
By installing the vibration suppressing portion symmetrically with respect to the center of gravity of the movable frame, there is an effect that the overall weight balance is matched and unnecessary tilting of the movable frame does not occur.

The PZT film constituting the piezoelectric material 20 may be formed by a sputtering method, a sol-gel liquid spin-coating method, or the like.
PZT has better conversion efficiency of electro-mechanical energy than other piezoelectric materials, and can be manufactured at low cost by the above-mentioned general manufacturing method.

In the present embodiment, the vibration suppressing portion 16 is provided at the connection portion as an example of a portion that moves due to the deformation of the meandering beam portion due to the application of the voltage, but the portion where the vibration suppressing portion is provided is not limited to this.
The portions that move due to the deformation of the meandering beam portion are the meandering beam portion itself, the connection portion, and the movable frame, and any of the moving portions as long as unnecessary vibration components for the vibration of the mirror portion 4 can be suppressed. May be the part.
The unnecessary vibration component includes a vibration component in a direction different from the vibration direction of the mirror unit 4, for example, a direction orthogonal to the above-described direction.

A second embodiment will be described with reference to FIGS.
The same parts as those of the above-described embodiment are denoted by the same reference numerals, and the description of the configuration and the function already described is omitted, and only the main part will be described.
As shown in FIG. 9, the optical deflector 30 according to the present embodiment is a two-axis scanning type optical deflector, and the mirror unit 4 is provided in the movable frame 6 of the optical deflector 2 shown in FIG. It has a configuration to rotate and vibrate around.
More specifically, one end of the movable frame 6 is fixed to the mirror portion 4 and serves as a pair of elastic support members that support the mirror portion 4 so that the mirror portion 4 can vibrate in a direction orthogonal to the vibration direction due to the deformation of the meandering beam portion. And a pair of drive beams 36, 38 having one end fixed to the other end of the torsion bars 32, 34.

The other ends of the drive beams 36 and 38 are integrally connected to the movable frame 6. The mirror section 4, the torsion bars 32, 34, and the drive beams 36, 38 are operable by forming grooves in the movable frame 6.
A piezoelectric member 40 is provided on the surfaces of the drive beams 36 and 38 in the same manner as the beam portion of the meandering beam portion, and is configured to be deformed by applying a voltage.
By driving the drive beams 36 and 38, the torsion bars 32 and 34 supporting the mirror unit 4 are twisted, and the mirror unit 4 rotationally vibrates around the Y axis.
The driving beams 36 and 38 are driven by sine waves, and the rotation of the mirror unit 4 utilizes mechanical resonance.

  The configuration of the vibration suppressing section in the connection sections C1 and C2 is the same as in the above embodiment. In the present embodiment, since the mirror is of the biaxial scanning type, there are two types of vibration directions of the mirror unit 4, the main scanning direction and the sub-scanning direction. And unnecessary vibration components for the respective vibrations in the sub-scanning direction.

In the optical deflector 30 of the present embodiment, the mirror unit 4 is rotated and oscillated at 20 kHz by the torsion of the torsion bars 32 and 34 by the application of the sine wave voltage of 20 kHz.
Regarding the rotation angle of the light reflection surface, the light reflection surface can be operated so as to obtain a rotation with a mechanical shake angle of ± 13 °.
On the other hand, by driving the first meandering beam portion 10 and the second meandering beam portion 12, the movable frame 6 rotates and vibrates around the X axis, and accordingly, the mirror portion 4 also rotates around the X axis. Vibrate.

In the optical deflector 30, a voltage is applied by a sawtooth wave to every other piezoelectric member 14 independently provided in each meandering beam portion of the meandering beam portion, and non-resonant driving is performed.
In such raster scanning by non-resonant driving, operation can be performed by a sawtooth wave of 60 Hz.
As shown in FIG. 10, the laser scanning in two axial directions becomes possible by the sinusoidal vibration S caused by the mechanical resonance in the Y direction and the rotation caused by the non-resonant drive NS in the X direction. Reference numeral 62 indicates a projection plane.

  In each of the embodiments described above, the vibration suppressing portion has a rectangular parallelepiped shape with a rectangular side surface, but the present invention is not limited to this. For example, as shown in FIG. 11, a vibration suppressing portion 16 ′ in which the thickness H gradually increases from the beam portion side of the meandering beam portion toward the connection portion may be used.

FIG. 12 shows a mounting form of the optical deflector 2.
The optical deflector 2 is covered by a package member 42. A resin or ceramic material is used for the package member 42.
The upper and lower electrodes of the optical deflector 2 are electrically connected to a drive circuit 44, and a voltage is applied between the upper and lower electrodes using the drive circuit 44.

A third embodiment (two-dimensional image display device) will be described with reference to FIGS.
FIG. 13 shows a projector 50 as a two-dimensional image display device.
In the projector 50, the light emitted from each of the red laser light source 52, the green laser light source 54, and the blue laser light source 56 is emitted by the collimator lens 58 as parallel light.
Specifically, a light source with a wavelength of 640 nm as a red laser, a wavelength of 520 nm as a green laser, and a wavelength of 450 nm as a blue laser was used.
The collimated laser light is incident on the optical path combining means 60. The optical path combining means 60 combines the three optical paths into one optical path, and uses an optical path combining prism such as a dichroic mirror.

The optical path combining means 60 has three reflecting surfaces. The combined laser light is two-dimensionally scanned with the incident laser light by a two-axis scanning type optical deflector 30 as two-dimensional scanning means for drawing an image, and an image is formed on a screen 62 as a projection surface. I do.
The formation of an image on the screen 62 is performed by two-dimensional optical scanning of laser light by the optical deflector 30 and intensity modulation of each laser light source.
At this time, the intensity modulation signal of each light source is sent from the LD driving unit 64, and the light scanning direction of the light deflector 30 on the screen 62 is sent from the optical deflector driving unit 66.
The control of the LD and the optical deflector 2 for forming an image is performed by the control unit 68. 13 and 14, reference numeral 70 denotes a power supply.

FIG. 14 shows a head-up display 72 as a two-dimensional image display device.
In the head-up display 72, a microlens array 74 is used as a screen, and an image is formed on the microlens array 74.
The observer 76 can visually recognize the virtual image 82 in which the image is enlarged via the projection mirror 78 and the combiner 80 as a translucent member ahead of the combiner 80.

In this case, since the laser light is diffused by the microlens array 74, the virtual image 82 with reduced speckle noise can be visually recognized.
Although a combiner is generally installed as a translucent member, a window glass of a vehicle can be used for a head-up display for a vehicle.

A fourth embodiment (optical scanning device) will be described based on FIG.
A laser beam from a laser element 84 as a light source passes through a collimating optical system 86 and is deflected by the optical deflector 2.
The deflected beam forms a spot image on a scanned surface 94 such as a photosensitive drum by an imaging optical system including an fθ lens 88 as a first lens, a toroidal lens 90 as a second lens, and a mirror 92. .
Instead of the optical deflector 2, a biaxial scanning type optical deflector 30 may be used.

A fifth embodiment (image forming apparatus) will be described with reference to FIG.
The optical scanning device 100 scans the surface (scanned surface) of the photosensitive drum 102 as an image carrier with one or a plurality of laser beams modulated by a recording signal in the axial direction of the drum.
The photosensitive drum 102 is driven to rotate in the direction of the arrow, and the surface charged by the charging unit 104 is optically scanned by the optical scanning device 100 based on image information to form an electrostatic latent image.
The electrostatic latent image is visualized into a toner image by a developing unit 106, and the toner image is transferred by a transfer unit 108 to a recording sheet 110 as a transfer target. The transferred toner image is fixed on the recording paper 110 by the fixing unit 112.
The cleaning unit 114 removes residual toner from the surface of the photosensitive drum 102 that has passed through the portion facing the transfer unit 108.

A configuration using a belt-shaped photoconductor instead of the photoconductor drum 102 is also possible.
Further, it is also possible to adopt a configuration in which the toner image is temporarily transferred to a transfer medium other than the recording paper, and the toner image is transferred from the transfer medium to the recording paper and fixed.

The optical scanning device 100 includes a light source 116 that emits one or a plurality of laser beams modulated by a recording signal, a light source driving unit 118 that modulates the light source 116, and the optical deflector 2.
Further, the optical scanning device 100 includes an imaging optical system 120 for imaging the light beam from the light source 116 on the light reflecting surface of the light deflector 2, and the photosensitive drum 102 And a scanning optical system 122 for forming an image on the surface.
The optical deflector 2 is incorporated in the optical scanning device 100 in a form mounted on a circuit board 126 together with an integrated circuit 124 for driving the optical deflector 2.
Instead of the optical deflector 2, a biaxial scanning type optical deflector 30 may be used.

The optical deflector according to the present invention consumes less power for driving as compared with the rotary polygon mirror, and thus is advantageous for power saving of the image forming apparatus.
Since the wind noise when the mirror unit 4 of the optical deflector vibrates is smaller than that of the rotary polygon mirror, it is advantageous for improving the quietness of the image forming apparatus.
The optical scanning device according to the present invention requires much less installation space than the rotary polygon mirror, and the amount of heat generated by the optical deflector is small, so that miniaturization is easy.
Therefore, it is advantageous for downsizing the image forming apparatus.
Note that a recording paper transport mechanism, a photosensitive drum driving mechanism, a developing unit, a control unit such as a transfer unit, a driving system of a light source, and the like are the same as those of the conventional image forming apparatus, and thus are omitted in the drawing.

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

2, 30 Optical deflector 4 Mirror section 6 Movable frame 8 Support frame 10 First meandering beam section as meandering beam section 12 Second meandering beam section as meandering beam section 16, 16 'Vibration suppression section C1, C2 connection part 14 Piezoelectric member 32, 34 Torsion bar 36, 38 as elastic support member 36, 38 Driving beam 52, 54, 56 Light source 50 Optical path synthesizing means 62 Screen as projection surface 84 Laser element as light source 102 As image carrier Photoreceptor drum 106 developing means 108 transfer means

JP 2012-185314 A

Claims (7)

A mirror unit having a light reflecting surface,
A movable frame including the mirror unit,
A support frame for supporting the movable frame,
A meandering beam portion disposed between the movable frame and the support frame on both sides of the movable frame and having a folded shape,
With
One end of each of the meandering beam portions is fixed to the support frame, and the other end is fixed to the movable frame at each connection portion,
Each of the meandering beam portions has a configuration that is deformed by applying a voltage,
The mirror section vibrates around a rotation axis by the deformation of each of the meandering beam sections due to voltage application being transmitted through the movable frame,
Each of the meandering beam portions and each of the connection portions includes a first silicon layer formed at least integrally,
Each of the meandering beam portions has a piezoelectric member on the first silicon layer via a first silicon oxide layer,
Each of the connection portions is provided on a side of the first silicon layer opposite to a side on which the piezoelectric member is provided , via a second silicon oxide layer , the movable portion when the mirror portion is not vibrating. Optical deflectors each having a vibration suppressing unit including a second silicon layer for suppressing a vibration component on a surface of a frame and having a direction perpendicular to the rotation axis as a rotation axis . The optical deflector according to claim 1,
An optical deflector, wherein each of the connection portions is arranged so as to be point-symmetric about the mirror portion. The optical deflector according to claim 2 ,
An optical deflector wherein one end of each of the meandering beam portions is disposed so as to be point-symmetric with respect to the mirror portion. The optical deflector according to any one of claims 1 to 3,
In the movable frame,
A pair of elastic support members, one end of which is fixed to the mirror portion, and which supports the mirror portion so that it can vibrate in a direction orthogonal to a vibration direction due to deformation of the meandering beam portion;
A pair of drive beams having a configuration that is deformed by applying a voltage, one end of which is fixed to the other end of the elastic support member,
An optical deflector having: A light source for emitting a plurality of different wavelengths of laser light,
Light path combining means for combining the optical paths of the laser light into one,
Two-dimensional scanning means for scanning the synthesized laser light to draw an image,
With
5. A two-dimensional image display device, wherein the two-dimensional scanning means is the optical deflector according to claim 4, wherein the light deflector performs light deflection and projects an image on a projection surface. Light source,
An optical deflector for deflecting a light beam from the light source,
An imaging optical system for imaging the deflected light beam into a spot on the surface to be scanned,
With
An optical scanning device, wherein the optical deflector is the optical deflector according to any one of claims 1 to 4. An image carrier;
An optical scanning device that forms an electrostatic latent image on the image carrier based on image information;
Developing means for visualizing the electrostatic latent image,
Transfer means for transferring the visible image to a transfer object,
Has,
An image forming apparatus, wherein the optical scanning device is the optical scanning device according to claim 6.

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