JP3129219B2 - Optical scanner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanner that scans light by deflecting light, and more particularly, to an optical scanner having a small movable mirror that can be operated with a large amplitude and that is manufactured using silicon micromachining technology.

[0002]

2. Description of the Related Art Conventionally, as an optical scanner that can be miniaturized,
Several types of devices have been developed to rotate the mirror to deflect light. For example, as shown in JP-A-6-43368 and JP-A-6-180428, two orthogonal
A mirror having a rotational vibration system around two axes is known.
According to this mirror, there is an advantage that light can be deflected in two axial directions by one optical scanner. Further, the devices described in the above publications are characterized in that they are driven using electrostatic force. In such an apparatus, the driving electrodes are arranged with a slight gap immediately below the driven mirror, and one capacitor is formed by the mirror made of a conductor and the driving electrodes.

When a voltage is applied between the mirror and a drive electrode facing the mirror, an electrostatic force is generated between the mirror and the drive electrode, and the mirror is attracted to the drive electrode.
Therefore, the mirror causes a rotational movement about the rotation axis. The drive electrodes are provided for each of the two axes, and the rotational movement around each axis is performed by applying a control voltage between the drive electrode and the mirror corresponding to each axis.

A configuration example of a conventional optical scanner is shown in FIG.
This will be described with reference to FIG. FIG.
8 shows a conventional optical scanner disclosed in Japanese Patent Application Laid-Open No. 8-108, in which (a) is a plan view and (b) is a sectional view.

In FIG. 19, a conventional optical scanner includes a mirror 201 that reflects light and is displaceable in the X-axis direction, and an X-axis scanning beam 202 that supports the mirror 201 from both sides.
And an electrostatic attraction unit 203 integrally formed outside the X-axis scanning beam unit 202 and displaceable in the Y-axis direction orthogonal to the X-axis direction, and supporting the electrostatic attraction unit 203 from both sides. Beam part 204 for Y-axis scanning, X-axis and Y-axis direction drive electrodes 205 and 206 arranged at positions facing mirror 201 and the back surface of electrostatic attraction unit 203, and electrodes on which these drive electrodes are formed A substrate 207 and the driving electrodes 205 and 206
And the driving electrodes 205 and 2 existing between the
And a support spacer 209 for supporting the mirror so as not to bend with respect to the displacement of the mirror, and determining the gap between the mirror and the drive electrode.
It is composed of The mirror 201, the X- and Y-axis scanning beams 202 and 204, and the electrostatic attraction unit 203 are formed by forming a silicon substrate 210. Further, the wiring portions 211 of the driving electrodes 205 and 206 are formed on a plane where no electrostatic force acts on the mirror 201.

[0006]

In the conventional optical scanner utilizing static electricity, the electrostatic force is inversely proportional to the square of the distance between the mirror and the drive electrode, and therefore, a sufficient electrostatic force to drive the mirror is provided. Requires that a drive electrode be disposed through a narrow gap facing the mirror. For this reason, the movement of the mirror is limited by the contact with the drive electrode, and there is a problem that the rotation angle of the mirror cannot be set large.

In the case of controlling the rotation of the two axes, conventionally, it is necessary to arrange a plurality of independent drive electrodes for controlling the respective rotations and supply an independent voltage to each electrode. To prevent the electrostatic force of the wiring portion from acting on the mirror, see Japanese Patent Application Laid-Open No. 6-180428.
As shown in (1), the wiring section needs to be formed on a different plane from the drive electrodes, and the structure is complicated.

In a two-dimensional optical scanner having a portion driven at a high frequency among portions driven at a low frequency, a rotary support supporting the portion driven at a low frequency has an elongated rod-shaped torsion. It is formed of a bar (torsion bar) and has not only a small stiffness in the rotation direction (twist direction) but also a small stiffness in the bending direction (flexion direction). In such a configuration, when the driving frequencies of the rotational motion around the two axes are significantly different, if an electrostatic force is generated to cause the rotational motion of the rotary vibration system having a high resonance frequency, the rotation at the target high resonance frequency is performed. The support of the rotating vibration system driven at a low frequency easily bends before the force occurs. As a result, a translational motion occurs as a whole mirror, and it is impossible to efficiently cause a rotational motion of the mirror. As a method for preventing this, in the invention described in JP-A-6-180428, a support spacer is provided at the center of the mirror. However, it is necessary to accurately adjust the support spacer to the position of the rotation axis of the mirror. However, there was a problem that the production was complicated and the production became difficult.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention has a simple structure, can easily drive the rotation of the mirror, and can increase the rotation angle of the mirror for deflecting light. To provide an optical scanner.

[0010]

In order to achieve the above object, a first optical scanner according to the present invention comprises a plate- like mirror for reflecting light, and a mirror positioned on a straight line on both sides of the mirror. A pair of rotary supports, the pair of rotary supports are connected, a frame surrounding the periphery of the mirror, and a device for applying a translational motion to the frame, the mirror,
A pair parallel to the mirror including the pair of rotating supports is
Have an asymmetric mass distribution on the front and back, and the translational vibration of the device
Is a straight line connecting the pair of rotating supports in parallel with the mirror.
It is characterized by being generated along the Y-axis direction orthogonal to the line .

Further, the first optical scanner has a function of reflecting light.
And a plate-shaped mirror for
A pair of rotating supports for supporting both sides, and the pair of rotating supports;
A frame part to which a holding body is connected, surrounding a periphery of the mirror,
A device for applying a translational motion to the frame portion, wherein the mirror comprises:
Left and right asymmetrical with respect to the straight line connecting the pair of rotating supports
Before having a mass distribution and including the pair of rotating supports
Has an asymmetric mass distribution with respect to the plane parallel to the mirror.
However, the translational vibration of the device is directed to a plane parallel to the mirror.
In the Z-axis direction intersecting and in parallel with the mirror,
Occurs along the Y-axis direction orthogonal to the straight line connecting the rotating supports
May be performed.

In these inventions, the apparatus for applying translational vibration to the frame generates translational vibration having a frequency equal to or close to a resonance frequency of a vibration system constituted by the mirror and the pair of rotary supports. Preferably, it is Further, the device may be a piezoelectric actuator or an electric actuator.
It may be a magnetic actuator.

Further, a second optical scanner according to the present invention comprises a plate- shaped mirror for reflecting light, a pair of Y-axis rotating supports positioned on a straight line and supporting both sides of the mirror,
A pair of Y-axis rotating supports connected to each other, a plate-shaped intermediate supporting portion surrounding the periphery of the mirror in a plane parallel to the mirror, and a straight line connecting the pair of Y-axis rotating supports parallel to the mirror; A pair of X-axis rotation supports, which are positioned on a straight line perpendicular to and support both sides of the intermediate support portion, and a frame portion to which the pair of X-axis rotation supports are connected and surrounds the periphery of the intermediate support portion And a device for applying a translational motion to the frame portion,
The mirror includes the pair of Y-axis rotation supports.
Has an asymmetric mass distribution on the front and back with respect to the plane parallel to the
The intermediate support portion is configured to directly connect the pair of X-axis rotation supports.
Having a mass distribution that is asymmetrical with respect to the line,
The mirror and the pair of Y-axis rotating supports
A frequency that is the same as or near the resonance frequency of the first vibration system
An X-axis parallel to a straight line connecting the pair of X-axis rotation supports
Means for generating translational vibration along a direction;
A dynamic system, the intermediate support portion, and the pair of X-axis rotation support members.
Same or close to the resonance frequency of the configured second vibration system
At a frequency of Z axis perpendicular to a plane parallel to the mirror
Means for generating translational vibration along the axis .

Further, the second optical scanner has a function of reflecting light.
And a plate-shaped mirror for
A pair of Y-axis rotating supports for supporting both sides,
A pivoting support is connected and forward in a plane parallel to the mirror.
A plate-shaped intermediate support surrounding the periphery of the mirror, and the mirror
And is perpendicular to a straight line connecting the pair of Y-axis rotation supports.
To support both sides of the intermediate support section.
A pair of X-axis rotation supports, and the pair of X-axis rotation supports
Are connected, a frame portion surrounding the periphery of the intermediate support portion,
A device for applying a translational motion to the frame portion, wherein the mirror comprises:
A plane parallel to the mirror including the pair of Y-axis rotating supports
The intermediate support portion has an asymmetric mass distribution with respect to the front and back
And the intermediate support portion including the pair of X-axis rotation supports.
It has a mass distribution that is asymmetrical with respect to the parallel surface,
Is composed of the mirror and the pair of Y-axis rotating supports.
Of the same or close to the resonance frequency of the first vibration system
The wave number is parallel to a straight line connecting the pair of X-axis rotation supports.
Means for generating translational vibration along the X-axis direction;
Vibration system, the intermediate support portion, and the pair of X-axis rotation support members
Or the same as the resonance frequency of the second vibration system
A straight line connecting the pair of Y-axis rotating supports at a frequency near
Means for generating translational vibration along the Y-axis direction parallel to
It may be characterized by having.

[0015]

[0016]

Further, a third optical scanner according to the present invention includes a plate- like mirror for reflecting light, a pair of Y-axis rotating supports positioned on a straight line and supporting both sides of the mirror,
The pair of Y-axis rotation supports are connected, and a plate-shaped intermediate support portion surrounding the periphery of the mirror in a plane parallel to the mirror, and positioned parallel to a straight line connecting the pair of Y-axis rotation supports. A pair of X-axis rotation supports, each of which is a cantilever that supports one side of the intermediate support, and a frame that connects the pair of X-axis rotation supports and surrounds the periphery of the intermediate support; A device for applying a translational movement to the part, wherein the mirror comprises:
A pair of Y-axis rotating supports and a plane parallel to the mirror are paired.
The device has an asymmetrical mass distribution,
And a pair of Y-axis rotation supports
At a frequency that is the same as or near the resonance frequency of the vibration system,
A straight line parallel to the mirror and connecting the pair of Y-axis rotating supports;
Means for generating translational vibration along the orthogonal X-axis direction;
The first vibration system, the intermediate support, and the pair of X-axis
The same as the resonance frequency of the second vibrating system
Orthogonal to the plane parallel to the mirror at one or more frequencies
Means for generating translational vibration along the Z-axis direction
It is characterized by that.

Further, the third optical scanner has a function of reflecting light.
And a plate-shaped mirror for
A pair of Y-axis rotating supports for supporting both sides,
A pivoting support is connected and forward in a plane parallel to the mirror.
A plate-shaped intermediate supporting portion surrounding the periphery of the mirror;
The intermediate support is positioned parallel to a straight line connecting the Y-axis rotation supports.
A pair of X-axis rotating supports, each of which is a cantilever supporting one side of the holding portion
The holding body and the pair of X-axis rotation supports are connected, and the
A frame that surrounds the periphery of the support, and a translational motion applied to the frame.
And a mirror for rotating the pair of Y-axes.
Front and back asymmetric with respect to the plane parallel to the mirror including the support
Mass distribution, the intermediate support portion, the pair of X-axis
Table with respect to a plane parallel to the intermediate support section including the rotary support
A back-asymmetric mass distribution, wherein the device is
A first vibration system including the pair of Y-axis rotation supports
At a frequency equal to or near the resonance frequency of the mirror,
And is perpendicular to a straight line connecting the pair of Y-axis rotation supports.
Means for generating translational vibration along the X-axis direction,
1. The vibration system, the intermediate support portion, and the pair of X-axis rotation supports
Not the same as the resonance frequency of the second vibration system composed of the body
At a frequency close to the distance between the pair of Y-axis rotating supports.
Means for generating translational vibration along the Y-axis direction parallel to the line;
May be provided.

[0019]

[0020]

In the above-mentioned second and third scanners
Means for generating translational vibration along the X-axis direction;
Means for generating translational vibration along the Y-axis direction are
Piezo or electromagnetic actuator
The piezoelectric actuator or the electromagnetic actuator
The drive signal of the motor generates a periodic electrical signal,
The amplitude and phase of the periodic electric signal are adjusted.

[0022]

[0023]

[0024]

(Operation) The present invention provides two mirrors supported by an externally applied translational motion by making the mass distribution of a mirror supported at both ends by a pair of mirrors wait for asymmetry. It uses the principle of generating a rotational moment about a connecting line as an axis and rotating the mirror.

In particular, when a translational vibration having a frequency equal to the resonance frequency of the rotary vibration system is applied, a rotational motion close to a regular sine wave having a very large rotational angle can be obtained with a small driving force.

When light is deflected in two axial directions, it is necessary to control the amplitude and phase of the rotational motion of the two vibration systems independently. However, the resonance frequencies of the two vibration systems are different from each other. Thus, by performing mechanical vibration mode separation, it is possible to independently control the amplitude and phase of the two rotational motions using a single translational vibration generating device. For example,
Assuming that the resonance frequency of rotation around the X axis is 60 Hz and the resonance frequency of rotation around the Y axis is 15 kHz, among the frequency components of the translational vibration applied to the frame portion, the vibration amplitude and phase of 60 Hz are controlled to control the X axis. The amplitude and phase of the rotation around can be controlled, and the amplitude and phase of the rotation around the Y axis can be controlled independently by controlling the amplitude and phase of 15 kHz.

Further, in general, when one structure is constituted by a part driven at a high frequency within a part driven at a low frequency, when one structure is applied with an external force, the structure becomes low. Since the part driven by the frequency becomes a low-pass filter and absorbs the high frequency component, the driving force of the high frequency is not transmitted to the part to be driven at the high frequency. Have difficulty.
However, in the present invention, utilizing the fact that the stiffness in the longitudinal direction of a rotating support having a low resonance frequency is much greater than the stiffness in the rotating direction, translational vibration is applied along the longitudinal direction of the rotating support. With such a configuration, a high-frequency driving force can be transmitted to the inside without being absorbed, and the rotational motion of a portion having a high resonance frequency can be easily driven.

Hereinafter, embodiments of the present invention and the present invention will be described.
A series of reference embodiments will be described with reference to the drawings.

( Embodiment 1 ) FIG. 1 is a perspective view schematically showing the configuration of an optical scanner according to Embodiment 1 of the present invention. The optical scanner of the form shown in this figure has a small movable mirror formed of a silicon chip and having a size of about 5 mm square and weighing several milligrams in total. The small movable mirror is a micromirror 1 having a size of about 2 mm square, and the micromirror 1 is distributed so as to have an asymmetric mass distribution.
A pair of X-axis rotation supports 2 having a width of 10 μm, a thickness of 5 μm, and a length of 300 μm, which are located on an axis parallel to the axis and support both sides of the micromirror 1, are connected. And a frame portion 3 having a width of about 500 microns surrounding the periphery of the micromirror 1 formed integrally from a silicon chip. Here, “width” refers to the dimension in the lateral direction on a plane parallel to the XY plane in the figure, and “length” refers to X in the figure.
The dimension in the longitudinal direction on a plane parallel to the Y plane is referred to as “thickness”.
"" Means a dimension in a direction parallel to the Z-axis direction in FIG.

On the back side of the frame portion 3, a piezoelectric element 4 having a plane area about the same as that of the small movable mirror and a thickness of about 1 mm is joined. The total weight of the small movable mirror and the piezoelectric element 4 is about 1 g. The driving force required for the piezoelectric element 4 is from several microns to several tens of microns along the Z-axis as the amplitude of the vibration. As the preferable piezoelectric element 4, a laminated type, a bimorph type, a Mooney type, or the like is used. .

In such a form, when a voltage is applied to the piezoelectric element 4, the piezoelectric element 4 expands and contracts and vibrates in the Z-axis direction. This vibration is transmitted to the frame 3. The micro mirror 1 makes a relative movement with respect to the driven frame 3,
When the vibration component in the Z-axis direction is transmitted to the micromirror 1, the micromirror 1 has a mass distribution that is asymmetrical with respect to the axis formed by the X-axis rotation support 2. A rotational moment is generated in the mirror 1. In this way, the translational vibration applied to the frame 3 by the piezoelectric element 4 is converted into a rotational movement of the micromirror 1 about the X-axis rotary support 2.

When a normal television signal is reproduced by performing optical scanning using the micromirror 1, two optical scanners having the above configuration are used, and the driving frequency of each X-axis rotation is set to be different from the vertical scanning. It is set near 60 Hz and near 15 kHz for horizontal scanning.

When an electric signal having a voltage of about 20 V and corresponding to the resonance frequency is applied to the piezoelectric element 4, a current of several milliamps flows to cause a translational vibration.
Rotational vibration of the micromirror 1 which is close in degree occurs, and a light deflection angle of 20 degrees or more is obtained.

( First Embodiment) FIG. 2 is a perspective view schematically showing the structure of an optical scanner according to a first embodiment of the present invention. The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror distributes the micromirror 21 and the micromirror 21 so as to have a symmetric mass distribution, and a pair of X-axis rotational supports that support both sides of the micromirror 21 and are located on an axis parallel to the X-axis. A body 22, a frame 23 surrounding the periphery of the micromirror 21 to which the X-axis rotation support 22 is connected, and a rotating weight 25 provided on the opposite side of the mirror surface of the micromirror 21 from a silicon chip It is formed integrally. A piezoelectric element 24 that can vibrate in the Y-axis direction is joined to the back side of the frame portion 23.

That is, in the present embodiment, by forming the rotating weight 25 on the back surface of the micro mirror 21 having a mass distribution symmetrical with respect to a straight line connecting the pair of X-axis rotation supports 22, the micro mirror 21 It is characterized in that it has an asymmetric mass distribution on the front and back sides with respect to a plane parallel to the mirror 21 including the X-axis rotation support 22.

In the embodiment shown in FIG. 2, translational vibration along the Y-axis is applied to the frame 23 by the piezoelectric element 24, thereby causing the micromirror 21 to rotate around the X-axis rotation support 22. be able to. The rotating weight 35 may be formed by leaving a large amount of silicon when the mirror region is formed, or may be formed by depositing polysilicon or another metal.

( Second Embodiment) FIG. 3 is a perspective view schematically showing the configuration of an optical scanner according to a second embodiment of the present invention. The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror is a micro-mirror 31 and a pair of X-axis rotation supports that distribute the micro-mirror 31 so as to have an asymmetric mass distribution and are located on an axis parallel to the X-axis and support both sides of the micro-mirror 31. The body 32, a frame 33 surrounding the periphery of the micromirror 31 to which the X-axis rotation support 32 is connected, and a rotating weight 35 provided on the opposite side of the mirror surface of the micromirror 31 from a silicon chip It is formed integrally. A piezoelectric element 34 that can vibrate in the Y-axis and Z-axis directions is joined to the back side of the frame 33.

That is, in this embodiment, the X-axis rotation support 32
The center of gravity of the rotary vibration system centered on
And on a plane other than the plane parallel to the mirror 31 including the X-axis rotation support 32. In other words, the micro mirror 31 provided with the rotating weight 35
Is asymmetrical with respect to the axis passing through the X-axis rotation support 32, and at the same time, the rotating weight 35 is used for the surface parallel to the mirror 31 including the X-axis rotation support 32. The feature is that it is asymmetric. Therefore, the micromirror 31 generates a rotational movement about the X-axis rotation support 32 irrespective of the vibration along the Y-axis or the vibration along the Z-axis by the piezoelectric element 34. .

( Embodiment 2 ) FIG. 4 is a perspective view schematically showing a configuration of an optical scanner of Embodiment 2 related to the present invention. The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror is a micro-mirror 41 and a pair of Y-axis rotation supports that distribute the micro-mirror 41 so as to have an asymmetric mass distribution and are positioned on an axis parallel to the Y-axis and support both sides of the micro-mirror 41. An intermediate support 43 surrounding the micromirror 41 to which the body 42 and the Y-axis rotation support 42 are connected, and an axis parallel to the X axis, which distributes the intermediate support 43 so as to have an asymmetric mass distribution. A pair of X-axis rotating supports 44 positioned on the line to support both sides of the intermediate support 43,
The frame 45 surrounding the periphery of the intermediate support 43 to which the shaft rotation support 44 is connected is formed integrally from a silicon chip. A piezoelectric element 46 that can vibrate in the Z-axis direction is joined to the back side of the frame 45.

That is, this embodiment is characterized in that a small movable mirror has two rotation axes, and one optical scanner can perform two-dimensional optical scanning. In order to provide two independent rotational vibration systems, the small movable mirror is provided with an X-axis rotation support 42 and a Y-axis rotation support 43 which are at an angle of 90 degrees to each other in the same plane. The micro mirror 41 is Y
The mass distribution is asymmetrical with respect to the axis formed by the shaft rotation support 43. Further, the intermediate support portion 43 has a mass distribution that is asymmetrical with respect to the axis formed by the X-axis rotation support member 44.

When reproducing a normal video signal by performing optical scanning with the micromirror 41, the driving frequency of the X-axis rotation corresponding to vertical scanning is set to 60 Hz, and the driving frequency of the Y-axis rotation corresponding to horizontal scanning is set to 60 Hz. Set near 15 kHz.

When the piezoelectric element 46 causes translational vibration in the Z-axis direction, the micromirror 41 has a mass distribution asymmetrical with respect to the axis formed by the rotating support, so that a rotational moment is generated around the rotating support. The micromirror 41 performs a rotary motion about a rotary support.

Further, by driving the translational movement of the piezoelectric element 46 in the Z-axis direction by a signal obtained by synthesizing the resonance frequencies for rotating each of the two axes, the rotation of the mirror in the two axial directions can be performed by one piezoelectric element 46. Vibration can be efficiently excited.
Also in this case, a performance with an optical scanning angle of 10 degrees or more can be easily obtained.

( Third Embodiment) FIG. 5 is a perspective view schematically showing a configuration of an optical scanner according to a third embodiment of the present invention. The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror is a micromirror 51 and a pair of Y-axis rotation supports that distribute the micromirror 51 so as to have an asymmetric mass distribution and are located on an axis parallel to the Y-axis and support both sides of the micromirror 51. The intermediate support 53 surrounding the periphery of the micromirror 51 to which the body 52 and the Y-axis rotation support 52 are connected.
And distributing the intermediate support portion 53 to have an asymmetric mass distribution. The intermediate support portion 53 is located on an axis parallel to the X axis.
A pair of X-axis rotation support members 54 supporting both sides of the frame and a frame portion 55 surrounding the intermediate support portion 53 to which the X-axis rotation support members 54 are connected are formed integrally from a silicon chip.

A piezoelectric element 56 that can vibrate in the X-axis direction is joined to one side of the frame section 55 in the X-axis direction, and a piezoelectric element 57 that can vibrate in the Z-axis direction is mounted on the back side of the frame section 55. Are joined.

That is, this embodiment is characterized in that the piezoelectric elements are separately arranged for each axis instead of the second embodiment .

In this case, the piezoelectric element 56 is used to cause the micromirror 51 to rotate around the Y axis, and the piezoelectric element 57 is used to cause the micromirror 51 to rotate around the X axis. By arranging the piezoelectric elements for each axis in this way, it is possible to use individually the piezoelectric elements that wait for characteristics suitable for the resonance frequency of each rotary vibration system. Therefore, for example, by setting the drive frequency of each piezoelectric element to coincide with or be close to the resonance frequency of the rotary vibration system to be driven, the drive efficiency can be significantly improved.

As in the first embodiment, a rotation weight is added to the opposite side of the mirror surface of the micro mirror 51 so that the micro mirror 51 is parallel to the mirror 51 including the Y-axis rotation support member 52. When the surface has an asymmetric mass distribution with respect to the plane, rotation around the Y axis can be efficiently generated.

( Fourth Embodiment) FIG. 6 is a perspective view schematically showing a configuration of an optical scanner according to a fourth embodiment of the present invention. The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror is a micro-mirror 61 and a pair of Y-axis rotation supports that distribute the micro-mirror 61 so as to have an asymmetric mass distribution and are located on an axis parallel to the Y-axis and support both sides of the micro-mirror 61. The intermediate support 63 surrounding the micromirror 61 to which the body 62 and the Y-axis rotation support 62 are connected
And distributing the intermediate support 63 so as to have an asymmetric mass distribution. The intermediate support 63 is positioned on an axis parallel to the X axis.
A pair of X-axis rotation supports 64 supporting both sides of the intermediate support portion 63 and a frame portion 65 surrounding the intermediate support portion 63 to which the X-axis rotation support 64 is connected are formed integrally from a silicon chip.

This embodiment is characterized in that, instead of the third embodiment, the piezoelectric elements are separately arranged in the directions along the X axis and the Y axis. That is, a piezoelectric element 66 that can vibrate in the X-axis direction is joined to one side of the frame portion 65 in the X-axis direction, and a piezoelectric element that can vibrate in the Y-axis direction is connected to one side of the frame portion 55 in the Y-axis direction. The element 67 is joined.

In this case, the piezoelectric element 65 is used to cause the micromirror 61 to rotate around the Y axis, and the piezoelectric element 66 is used to cause the intermediate support 63 to rotate around the X axis.

As in the first embodiment, a rotating weight is added to the opposite side of the mirror surface of the micromirror 61 so that the micromirror 61 is parallel to the mirror 61 including the Y-axis rotating support 62. When the surface has an asymmetrical mass distribution with respect to the surface, rotation around the Y axis can be efficiently generated. Similarly, a rotation weight is added to the intermediate support portion 63 so that the intermediate support portion 63 However, even if it has a mass distribution that is asymmetrical with respect to a plane parallel to the intermediate support portion 63 including the X-axis rotation support 64, rotation around the Y-axis can be efficiently generated. In this way, when the mass distribution is asymmetrical with respect to a plane parallel to the XY plane, the arrangement of the piezoelectric elements according to the present embodiment is effective.

( Embodiment 3 ) When a low vertical frequency and a high horizontal light scanning frequency are required at the same time as in the reproduction of a video signal, it may be difficult to achieve a low frequency by a supporting method using a torsion bar.
In such a case, it is preferable that the rotary support of the rotary vibration system that handles a low frequency is formed of a cantilever. Including this reference form
The structure including the above-mentioned cantilever will be described up to the sixth embodiment below.

FIG. 7 shows the light of Reference Embodiment 3 related to the present invention.
It is the perspective view which represented typically the structure provided with the above-mentioned cantilever as a scanner . The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror is a micromirror 71 and a pair of Y-axis rotation supports that distribute the micromirror 71 so as to have an asymmetric mass distribution and are located on an axis parallel to the Y-axis and support both sides of the micromirror 71. The body 72 and the Y-axis rotation support 72 are connected,
An intermediate support 73 surrounding the periphery of the micromirror 71;
A pair of X-axis rotation supports 74, which are positioned on an axis parallel to the axis and support one side of the intermediate support 43,
A frame 75 surrounding the periphery of the intermediate support 73 to which 4 is connected
Are integrally formed from a silicon chip. Frame part 7
A piezoelectric element 76 capable of oscillating in the Z-axis direction is joined to the back side of 5.

In such an embodiment, a rotary vibration system having a low drive frequency is realized by the intermediate support 73 supported by the X-axis rotary support 74 which is a cantilever with respect to the frame 75. The Y-axis rotating support 72 is provided in the intermediate support 73.
The present embodiment is characterized in that the micromirrors 71 supported at both ends are disposed so as to have a mass distribution that is asymmetrical in the left and right directions with respect to the axis defined by.

The beam thickness of the cantilever beam serving as the X-axis rotation support 74 is 1 μm to several tens of microns, and the beam width is 1 μm.
It is about 0 microns. The length of the beam, depending on the drive frequency, is on the order of tens of microns to one millimeter.

Since the X-axis rotating support 74, which is a cantilever, can be easily moved in the Z-axis direction, the piezoelectric element 76 is displaced in the Z-axis direction to drive the micromirror 71 about the X-axis. Use for Since the micromirror 71 has an asymmetric mass distribution with respect to the axis formed by the Y-axis rotation support member 72, the micromirror 71 is rotated around the Y-axis by applying vibration along the Z-axis. Therefore, by applying vibration in the Z-axis direction, rotation about the X-axis and rotation about the Y-axis can be caused simultaneously.

( Fifth Embodiment) FIG. 8 is a perspective view schematically showing a configuration of an optical scanner according to a fifth embodiment of the present invention. The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror is a micro-mirror 81 and a pair of Y-axis rotation supports that distribute the micro-mirror 81 so as to have an asymmetric mass distribution and that are positioned on an axis parallel to the Y-axis and support both sides of the micro-mirror 81. Support 82 surrounding the periphery of micromirror 81 to which body 82 and Y-axis rotation support 82 are connected
And a pair of X-axis rotation supports 84 that are positioned on an axis parallel to the X-axis and support one side of the intermediate support 83, and the periphery of the intermediate support 83 to which the X-axis rotation support 84 is connected. The surrounding frame 55 is formed integrally from a silicon chip.

A piezoelectric element 86 that can vibrate in the X-axis direction is joined to one side of the frame section 85 in the X-axis direction, and a piezoelectric element 87 that can vibrate in the Z-axis direction is provided on the back side of the frame section 85. Are joined.

That is, the present embodiment is characterized in that the rotary support of the rotary vibration system that handles the low frequency is formed of a cantilever, and the piezoelectric elements are separately arranged for each axis instead of the third embodiment. There is.

When the piezoelectric elements are arranged for each axis as described above,
Since the driving frequency of each piezoelectric element can be made different, for example, the driving frequency of the piezoelectric element 87 that causes vibration about the X axis is 60 Hz, and the driving frequency of the piezoelectric element 86 that causes vibration about the Y axis is 15 kHz. Can be set to Naturally, when the driving frequency of the piezoelectric element is adjusted to the resonance frequency of the rotary vibration system, a large amplitude can be obtained.

As in the first embodiment, a rotating weight is added to the opposite side of the mirror surface of the micro mirror 81 so that the micro mirror 81 is parallel to the mirror 81 including the Y-axis rotating support 82. When the surface has a mass distribution that is asymmetrical with respect to the surface, rotation around the Y axis can be efficiently generated.

( Sixth Embodiment) FIG. 9 is a perspective view schematically showing the configuration of an optical scanner according to a sixth embodiment of the present invention. The optical scanner of the embodiment shown in this figure has a small movable mirror formed of a silicon chip, as in the first embodiment . The small movable mirror is a micro-mirror 91 and a pair of Y-axis rotation supports that distribute the micro-mirror 91 so as to have an asymmetric mass distribution and are located on an axis parallel to the Y-axis and support both sides of the micro-mirror 91. Intermediate support 93 surrounding the periphery of micromirror 91 to which body 92 and Y-axis rotation support 92 are connected
And a pair of X-axis rotation supports 94 that are positioned on an axis parallel to the X-axis and support one side of the intermediate support 93, and the periphery of the intermediate support 93 to which the X-axis rotation support 94 is connected. The surrounding frame 95 is formed integrally from a silicon chip.

A piezoelectric element 96 that can vibrate in the X axis direction is joined to one side of the frame section 95 in the X axis direction.
A piezoelectric element 9 that can vibrate in the Y-axis direction is provided on one side in the axial direction.
7 are joined.

That is, in the present embodiment, the rotary support of the rotary vibration system that handles the low frequency is constituted by a cantilever, and the piezoelectric elements are separately arranged in the directions along the X axis and the Y axis. There is a feature.

In general, a pair of cantilevers supporting one side of the intermediate support 93 as described above have a significantly smaller stiffness in the Z-axis direction than other axial directions. There is a property that a Z-axis translation frequency component higher than the resonance frequency is not introduced inside. For this reason, in this embodiment, the piezoelectric element 96 or the piezoelectric element 97 is arranged so that the vibration direction of the piezoelectric element 96 or the piezoelectric element 97 occurs in a direction different from the Z-axis direction in which the X-axis rotation support 94 easily vibrates. With this arrangement, even when the bending stiffness of the X-axis rotation support 94 around the X-axis is extremely small, the stiffness along the Y-axis, which is the longitudinal direction of the X-axis rotation support 94, or the X-axis direction Since the stiffness is very large, the vibration of the piezoelectric element disposed outside the frame 95 can be effectively applied to the micromirror 91 inside the frame 95. The micromirror 91 inside obtains a rotational force due to the asymmetry of the mirror, but if a part or all of one surface of the micromirror 91 is provided with a rotating weight, the micromirror 91 efficiently rotates around the Y axis. Can be done. Similarly, if a part or all of one surface of the intermediate support part 93 is provided with a weight for rotation, the rotation can be efficiently generated around the X axis.

[0068] (Reference Embodiment 4) Structure Examples for from this reference embodiment to the eleventh embodiment of creating a vibration system having an asymmetric mass distribution.

FIG. 10 is a perspective view schematically showing a small movable mirror constituting an optical scanner according to a fourth embodiment relating to the present invention. The small movable mirror in the form shown in this figure includes a micromirror 101, a pair of X-axis rotation supports 102 located on an axis parallel to the X-axis and supporting both sides at the center of the micromirror 101, Frame 1 surrounding the periphery of micromirror 101 to which rotating support 102 is connected
03 is formed integrally from a silicon chip. Then, the micro mirror 101 is moved to the X-axis rotation support 102.
A hole 104 or a groove is provided on the surface of the micromirror 101 so as to have a mass distribution that is asymmetrical with respect to the axis defined by.

The size of the hole 104 is the size of the micro mirror 101.
Depending on the size, a range of several microns to several hundred microns is desirable. If a through hole is formed, the area of the mirror is reduced. Therefore, it is desirable that the hole be formed from the side opposite to the mirror surface and be stopped halfway. Of course, after digging a hole, the space of the hole may be filled with a material having a different mass density. In this step, a polishing process used for the embedded wiring used in the VLSI may be used. The vibration effect increases as the holes are provided in the periphery of the micromirror.

( Embodiment 5 ) FIG. 11 is a perspective view schematically showing a small movable mirror constituting an optical scanner of Embodiment 5 related to the present invention.
The small movable mirror in the form shown in this figure includes a micromirror 111, a pair of Y-axis rotating supports 112 located on an axis parallel to the Y-axis and supporting both sides at the center of the micromirror 111, An intermediate support 113 surrounding the micromirror 111 to which the rotary support 112 is connected;
A pair of X-axis rotation supports 114, which are located on an axis parallel to the X-axis and support both sides at the center of the intermediate support 113, and the periphery of the intermediate support 113 to which the X-axis rotation support 114 is connected. The surrounding frame 115 is formed integrally from a silicon chip. Then, the holes 11 are formed on the surface of the micromirror 111 so that the micromirror 111 has an asymmetric mass distribution with respect to the axis formed by the Y-axis rotation support 112.
6 or grooves are provided, and
However, a hole 117 or a groove is provided on the surface of the intermediate support portion 113 so as to have an asymmetric mass distribution with respect to the axis formed by the X-axis rotation support 114. In other words,
The hole 116 or the groove is positioned so that the center of gravity of the micromirror 111 is shifted from the axis formed by the Y-axis rotation support 112, and the hole 117 or the groove is formed by the center of gravity of the intermediate support 113 from the axis formed by the X-axis rotation support 112. Are positioned so as to shift.

( Seventh Embodiment) FIG. 12 is a perspective view schematically showing a small movable mirror constituting an optical scanner according to a seventh embodiment of the present invention. The small movable mirror in the form shown in this figure includes a micromirror 121, a pair of Y-axis rotating supports 122 located on an axis parallel to the Y-axis and supporting both sides at the center of the micromirror 121, and a Y-axis. An intermediate support portion 123 surrounding the periphery of the micro mirror 121 to which the rotary support member 122 is connected, and a pair of X-axis rotary supports located on an axis parallel to the X axis and supporting both sides at the center of the intermediate support portion 123. The body 124 and a frame 125 surrounding the intermediate support 123 to which the X-axis rotation support 124 is connected are formed integrally from a silicon chip. The micromirror 111 has an asymmetric mass distribution with respect to the axis formed by the Y-axis rotation support 112, and the intermediate support 113 to which the micromirror 121 is connected is formed by the X-axis rotation support 124. A hole 126 or a groove is provided in a corner area of the biaxially supported micromirror 121 so as to have an asymmetric mass distribution with respect to the axis. When the holes 126 or the grooves are arranged in this manner, the micro mirror 121 rotates around the X axis or the Y axis when vibration is applied in the Z axis direction.

( Eighth Embodiment) FIG. 13 is a perspective view of a small movable mirror constituting an optical scanner according to an eighth embodiment of the present invention as viewed from the side opposite to the mirror surface. The small movable mirror in the form shown in this figure includes a micromirror (not shown), a pair of Y-axis rotating supports 132 that are located on an axis parallel to the Y-axis and support both sides at the center of the micromirror, The shaft rotating support 132 is connected,
An intermediate support 133 surrounding the periphery of the micromirror, a pair of X-axis rotation supports 134 located on an axis parallel to the X-axis and supporting both sides at the center of the intermediate support 133, and an X-axis rotation support 134 Is connected to the frame 135 surrounding the periphery of the intermediate support 133, and the micromirror is arranged such that the micromirror has a mass distribution that is asymmetrical with respect to a plane parallel to the mirror including the Y-axis rotation support 132. The rotating weight 131 disposed on the entire surface of the mirror opposite to the mirror surface is integrally formed of a silicon chip.

The rotating weight 131 is formed at the same time as the frame 135 by anisotropic etching, which is a well-known method in a semiconductor acceleration sensor manufacturing process and the like.
Of course, after forming the thin-film micromirror, the rotating weight 131 may be added using a resin such as plating and photoresist.

( Ninth Embodiment) FIG. 14 is a perspective view of a small movable mirror constituting an optical scanner according to a ninth embodiment of the present invention as viewed from the side opposite to the mirror surface. The small movable mirror in the form shown in this figure includes a micromirror 141, a pair of Y-axis rotating supports 142 located on an axis parallel to the Y-axis and supporting both sides at the center of the micromirror 141, and a Y-axis. Intermediate support part 14 surrounding the periphery of micromirror 141 to which rotary support 142 is connected
3 and an intermediate support portion 143 positioned on an axis parallel to the X axis.
X-axis rotating supports 144 supporting both sides at the center of the body
And the intermediate support 1 to which the X-axis rotation support 144 is connected.
A frame portion 145 surrounding the periphery of the micromirror 43;
The rotation weight 141 disposed on the opposite side of the mirror surface of the micromirror so as to have a mass distribution that is asymmetrical with respect to the surface parallel to the mirror 141, including the Y-axis rotation support 142, It is formed integrally from a chip.
In particular, in this embodiment, instead of the eighth embodiment, the mass distribution of the small movable mirror is not only on the plane parallel to the mirror 141 including the Y-axis rotation support 142, but also on the X-axis rotation support 144. It is also characterized by being asymmetric with respect to the axis defined by. With this configuration, the vibration in the X-axis direction can be converted into rotation about the Y-axis, and the vibration in the Z-axis direction can be converted into rotation about the X-axis.

( Tenth Embodiment) FIG. 15 is a perspective view schematically showing a small movable mirror constituting an optical scanner according to a tenth embodiment of the present invention. The small movable mirror in the form shown in this figure includes a micromirror 151, a pair of Y-axis rotating supports 152 located on an axis parallel to the Y-axis and supporting both sides at the center of the micromirror 151, and a Y-axis. An intermediate support 153 surrounding the periphery of the micromirror 151 to which the rotary support 152 is connected;
A pair of X-axis rotation supports 154 that are positioned on an axis parallel to the axis and support both sides at the center of the intermediate support 153, and surround the periphery of the intermediate support 153 to which the X-axis rotation support 154 is connected. The frame 155 is formed integrally from a silicon chip. The micromirror 1 is arranged such that the micromirror 151 has a mass distribution that is asymmetrical with respect to a plane parallel to the mirror 151 including the Y-axis rotation support 142.
On the side opposite to the mirror surface of 21, there is provided a removed portion 156 or a groove formed by digging a silicon material constituting the micro mirror 121.

According to such an embodiment, it is generally difficult to leave the rotating weight on the micromirror 121 with high precision by etching, but it is easy to manufacture because the digging can be performed with high precision.

( Eleventh Embodiment) FIG. 16 is a perspective view schematically showing a small movable mirror constituting an optical scanner according to an eleventh embodiment of the present invention. The small movable mirror in the form shown in this figure includes a micro mirror 161, a pair of Y axis rotation supports 162 positioned on an axis parallel to the Y axis and supporting both sides at the center of the micro mirror 161, and a Y axis. An intermediate support 163 surrounding the micromirror 161 to which the rotary support 162 is connected;
A pair of X-axis rotation supports 164 that are located on an axis parallel to the axis and support both sides at the center of the intermediate support 163, and surround the periphery of the intermediate support 163 to which the X-axis rotation support 164 is connected. The frame 165 is formed integrally from a silicon chip. In particular, this embodiment replaces the tenth embodiment,
The mass distribution of the small movable mirror is not limited to the plane parallel to the mirror 161 including the Y-axis rotation support 162,
A removal portion 166 or a groove is formed in a part of the micro mirror 161 on the side opposite to the mirror so as to be asymmetric with respect to the axis formed by the shaft rotation support 164.

With this configuration, the vibration in the X-axis direction can be converted into rotation around the Y-axis, and the vibration in the Z-axis direction can be converted into rotation around the X-axis.

( Embodiment 6 ) As described in Embodiment 2 and Embodiment 3 above,
It is possible to simultaneously rotate around two rotation axes, such as around the X axis and around the Y axis, with two piezoelectric elements, but it is practically necessary to control the amplitude and phase of each rotation independently. .

FIG. 17 is a diagram showing a sixth embodiment related to the present invention.
And an optical scanner, illustrates the configuration of a driving method in the case of optical scanning in the two directions by a single piezoelectric element. In this case, the driving method includes an X-axis driving frequency generation circuit 171 and a Y-axis driving frequency generation circuit 171.
It has two frequency generating circuits, that is, a shaft driving frequency generating circuit 172. The generated driving signals are respectively introduced into amplitude / phase adjusting circuits 173 and 174, and the amplitude and phase are determined. After that, the electric signal synthesizing circuit 175
And is converted into one electric signal. Finally, the electric signal is amplified by the output circuit 176 and supplied to the piezoelectric element 177.

The generated waveform is basically a sine wave (sine wave), but may be a rectangular wave or a sawtooth wave. Further, these waveforms may be generated in an analog manner or in a digital manner. This driving method can receive an input signal for synchronizing a generated signal, and has, for example, a function of starting oscillation in synchronization with an external video signal.

[0083] Here (twelfth embodiment) illustrating a driving method required when having a piezoelectric element for each axis as in the embodiment of such third, fourth, fifth and sixth described above.

FIG. 18 is a configuration diagram showing a drive system in the case where a piezoelectric element is provided for each optical scanning axial direction as a twelfth embodiment of the optical scanner of the present invention. In the driving method in this case, the X-axis driving frequency generation circuit 181 and the Y-axis driving frequency
The signals generated by the shaft drive frequency generation circuit 182 are introduced into amplitude and phase adjustment circuits 183 and 184, respectively, where the amplitude and phase are adjusted. Thereafter, the electric signals are supplied to output circuits 185 and 186 for power amplification, respectively, and electric signals are supplied to the X-axis piezoelectric element 187 and the Y-axis piezoelectric element 188, respectively. The voltage supplied is on the order of a few volts to 100 volts and the current is up to several tens of milliamps.
A plurality of piezoelectric elements can be provided for each axis. For example, a piezoelectric element for giving a basic vibration amplitude and a piezoelectric element for performing amplitude control for coping with external disturbance. In this case, since the fluctuation is smaller than the reference amount, it is possible to reduce the power and circuit size required for the control.

In each of the embodiments described above, the piezoelectric element is used as the actuator for inducing the translational vibration applied to the small movable mirror. However, the present invention is not limited to this, and the present invention is not limited to the case where electromagnetic, heat, light, or the like is used. Needless to say, a similar effect is also observed. In addition, in the direction of the translational vibration, there are vibrations from other than the disclosed axis and combinations thereof, but needless to say, these are also included in the present invention.

The fixing of the piezoelectric element is performed firmly between the mirror and the mirror to be vibrated, but the connection with the package may be made by fixing a part of the piezoelectric element firmly, or the whole piezoelectric body including the mirror may be fixed. It may be floated from a package with a soft material such as silicone rubber and fixed.

[0087]

According to the present invention described above, the following effects can be obtained.

By removing the position of the center of gravity of the mirror or the position of the center of gravity of the intermediate support from the axis formed by a pair of rotary supports that support it, the translational vibration is converted into rotary motion. Can be awakened. If the driving frequency that causes translational vibration is matched to the resonance frequency of the rotary vibration system, it is possible to obtain a significantly large vibration, and by setting the resonance frequency of the two-axis rotary vibration system separately, Exercise can be controlled independently. Conventionally, a plurality of actuators were required to drive a multi-degree-of-freedom. However, since a single actuator can be used, the mirror structure can be significantly simplified. Therefore, the production is very simple and the cost can be reduced.

If the resonance driving frequencies are significantly different, the efficiency of the piezoelectric actuator is reduced when the same actuator is used. Therefore, when vibration is applied in a plurality of frequency regions, the overall efficiency is improved. Unlike a conventional actuator using static electricity, an actuator that vibrates from the outside is used, so that a very large force can be used as compared with a normal driving method using electrostatic force, and a scanning speed of 10 KHz and a scanning angle of 10 KHz. It is possible to easily realize an optical scanner that requires a high-speed and large-amplitude operation of a degree or more.

To create an asymmetric structure used to convert translational vibration applied from the outside into rotation, a method of supporting the mirror itself asymmetrically, adding a weight to a mirror whose mass distribution is equivalently supported, A method of providing holes or grooves can be used. Above all, if holes or grooves are provided in the mirror to realize an asymmetric mass distribution, the process is simple.

Driving at two different frequencies by using one translational vibration generating device requires only one electric circuit for driving, so that the electric circuit is simplified and the cost can be reduced.

When one structure has a rotational vibration system driven at a high frequency in a rotational vibration system driven at a low frequency, the stiffness in the longitudinal direction of the rotational support having a low resonance frequency increases. By making use of the fact that the stiffness is extremely large compared to the stiffness in the direction, translational vibration can be applied along the longitudinal direction of the rotating support, so that high-frequency driving force can be absorbed inside without being absorbed. It can transmit and can easily drive the rotational movement of the part having the high resonance frequency.

Although it is difficult to realize a low resonance frequency in a small area with the dual support structure of the rotary support, the low frequency can be obtained by coexisting the cantilever support structure and the double support structure in one structure. And high-frequency driving can be realized at the same time, and mirror scanning including both signals simultaneously (for example, horizontal and vertical scanning of a television)
Becomes possible.

The intermediate support portion, the weight portion, the beam thickness and the like do not need to be the same, and are adjusted to an appropriate value for the resonance frequency to be used.

Since no electrostatic force is used, the mirror surface does not need to be a conductor, and an organic material or the like can be used as the reflection film. The process is significantly simplified since there is no need to wire the mirror itself.

When the driving frequency of the translational vibration is combined with the resonance frequency of the piezoelectric element itself, the amplitude of the actuator itself increases when the same power is supplied, so that highly efficient driving is possible.

The resonance frequency of the rotary vibration system can be set to any frequency, and the horizontal frequency is set to 75 kHz and the vertical scanning frequency is set to 200H like a high definition image.
It is needless to say that z can be dealt with. When a piezoelectric element or the like is used for driving, it is possible to drive the mirror with very low power.However, if the voltage is increased, an amplitude of 30 degrees or more can be easily obtained with a power consumption of several milliwatts. it can. Naturally, when a larger mirror amplitude is required, the reflection angle can be increased by stacking multiple mirrors and performing multiple reflections.

The optical scanner according to the present invention can be used as a display device or an image pickup device for displaying an image by scanning light while simultaneously using a light emitting element and a light receiving element.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically illustrating a configuration of an optical scanner according to a first embodiment related to the invention.

FIG. 2 is a perspective view schematically showing a configuration of a first embodiment of the optical scanner of the present invention.

FIG. 3 is a perspective view schematically showing a configuration of a second embodiment of the optical scanner of the present invention.

FIG. 4 is a perspective view schematically illustrating a configuration of an optical scanner according to a second embodiment related to the invention.

FIG. 5 is a perspective view schematically showing a configuration of a third embodiment of the optical scanner of the present invention.

FIG. 6 is a perspective view schematically showing a configuration of a fourth embodiment of the optical scanner of the present invention.

FIG. 7 is a perspective view schematically showing a structure including a cantilever as an optical scanner according to a third embodiment related to the invention.

FIG. 8 is a perspective view schematically illustrating a configuration of an optical scanner according to a fifth embodiment of the present invention.

FIG. 9 is a perspective view schematically showing a configuration of a sixth embodiment of the optical scanner of the present invention.

FIG. 10 is a perspective view schematically showing a small movable mirror constituting an optical scanner according to a fourth embodiment relating to the present invention.

FIG. 11 is a perspective view schematically illustrating a small movable mirror constituting an optical scanner according to a fifth embodiment related to the invention.

FIG. 12 is a perspective view schematically showing a small movable mirror constituting a seventh embodiment of the optical scanner of the present invention.

FIG. 13 is a perspective view of a small movable mirror included in an optical scanner according to an eighth embodiment of the present invention, as viewed from a side opposite to a mirror surface.

FIG. 14 is a perspective view of a small movable mirror constituting an optical scanner according to a ninth embodiment of the present invention as viewed from a side opposite to a mirror surface.

FIG. 15 is a perspective view schematically showing a small movable mirror constituting a tenth embodiment of the optical scanner of the present invention.

FIG. 16 is a perspective view schematically showing a small movable mirror constituting an eleventh embodiment of the optical scanner of the present invention.

FIG. 17 is a configuration diagram illustrating a driving method in a case where one piezoelectric element performs optical scanning in two axial directions as an optical scanner according to a sixth embodiment related to the invention.

FIG. 18 is a configuration diagram showing a driving method when a piezoelectric element is provided for each optical scanning axial direction as a twelfth embodiment of the optical scanner of the present invention.

19A and 19B show a conventional optical scanner disclosed in Japanese Patent Application Laid-Open No. 6-180428, wherein FIG. 19A is a plan view and FIG. 19B is a sectional view.

[Explanation of symbols]

1,21,31,41,51,61,71,81,9
1,101,111,121,141,151,161
Micro mirror 2,22,32,44,54,64,74,84,9
4,102,114,124,134,144,15
4,164 X-axis rotation support 3,23,33,45,55,65,75,85,9
5,103,115,125,135,145,15
5,165 Frame part 4,24,34,46,56,57,66,67,7
6,86,87,96,97 Piezoelectric element 25,35,131 Rotating weight 42,52,62,72,82,92,112,12
2,132,142,152,162 Y-axis rotating support 43,53,63,73,83,93,113,12
3, 133, 143, 153, 163 Intermediate support portion 104, 116, 117, 126 Hole 156, 166 Removal portion 171, 181 X-axis drive frequency generation circuit 172, 182 Y-axis drive frequency generation circuit 173, 174, 183, 184 Amplitude adjustment circuit 175 Synthesis circuit 176, 185, 186 Output circuit 177 Piezoelectric element 187 X-axis piezoelectric element 188 Y-axis piezoelectric element

──────────────────────────────────────────────────続 き Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 26/10 101 G02B 26/08

Claims (10)

(57) [Claims] 1. A plate-shaped mirror for reflecting light, a pair of rotary supports positioned on a straight line and supporting both sides of the mirror, and the pair of rotary supports connected to each other, A frame portion surrounding the periphery, and a device for applying a translational motion to the frame portion, wherein the mirror has a mass distribution that is asymmetrical with respect to a plane parallel to the mirror, including the pair of rotating supports. An optical scanner, wherein the translational vibration of the device is generated along a Y-axis direction which is parallel to the mirror and orthogonal to a straight line connecting the pair of rotary supports. 2. A plate-shaped mirror for reflecting light, a pair of rotary supports positioned on a straight line and supporting both sides of the mirror, and the pair of rotary supports are connected to each other. A frame portion surrounding the periphery, and a device for performing a translational motion to the frame portion, wherein the mirror has a mass distribution asymmetrical with respect to a straight line connecting the pair of rotary supports, and Including a rotating support, having a mass distribution that is asymmetrical with respect to a plane parallel to the mirror, the translational vibration of the device is in a Z-axis direction orthogonal to the plane parallel to the mirror, and in a direction parallel to the mirror. The optical scanner is generated along a Y-axis direction orthogonal to a straight line connecting the pair of rotary supports. 3. The apparatus according to claim 1, wherein the device generates translational vibration having a frequency equal to or close to a resonance frequency of a vibration system configured by the mirror and the pair of rotating supports. An optical scanner as described. 4. The device according to claim 1, wherein the device is a piezoelectric actuator or an electromagnetic actuator.
The optical scanner according to the item. 5. A plate-shaped mirror for reflecting light, a pair of Y-axis rotation supports positioned on a straight line and supporting both sides of the mirror, and the pair of Y-axis rotation supports are connected. A plate-like intermediate support portion surrounding the periphery of the mirror in a plane parallel to the mirror, and positioned on a straight line parallel to the mirror and orthogonal to a straight line connecting the pair of Y-axis rotating supports, A pair of X-axis rotation supports that support both sides of the intermediate support, a pair of the X-axis rotation supports that are connected, and a frame that surrounds the periphery of the intermediate support; and a device that applies translational motion to the frame. The mirror has a mass distribution asymmetrical with respect to a plane parallel to the mirror, including the pair of Y-axis rotation supports, and the intermediate support portion includes the pair of X-axis rotation supports. The device has a mass distribution that is asymmetrical with respect to a straight line connecting the body, An X-axis direction parallel to a straight line connecting the pair of X-axis rotation supports at a frequency equal to or close to the resonance frequency of the first vibration system including the mirror and the pair of Y-axis rotation supports. Means for generating translational vibration along the axis, and a frequency equal to or close to a resonance frequency of a second vibration system constituted by the first vibration system, the intermediate support portion, and the pair of X-axis rotation supports. Means for generating translational vibration along a Z-axis direction orthogonal to a plane parallel to the mirror. 6. A plate-like mirror for reflecting light, a pair of Y-axis rotation supports positioned on a straight line and supporting both sides of the mirror, and the pair of Y-axis rotation supports are connected. A plate-like intermediate support portion surrounding the periphery of the mirror in a plane parallel to the mirror, and positioned on a straight line parallel to the mirror and orthogonal to a straight line connecting the pair of Y-axis rotating supports, A pair of X-axis rotation supports that support both sides of the intermediate support, a pair of the X-axis rotation supports that are connected, and a frame that surrounds the periphery of the intermediate support; and a device that applies translational motion to the frame. The mirror has a mass distribution asymmetrical with respect to a plane parallel to the mirror, including the pair of Y-axis rotation supports, and the intermediate support portion includes the pair of X-axis rotation supports. Including the body,
The apparatus has a mass distribution that is asymmetrical with respect to a plane parallel to the intermediate support, and the apparatus has the same resonance frequency as a first vibration system configured by the mirror and the pair of Y-axis rotating supports. Means for generating translational vibration at a frequency near or along an X-axis direction parallel to a straight line connecting the pair of X-axis rotary supports, the first vibration system, the intermediate support portion, and the pair of X-axes. A translational vibration is generated along a Y-axis direction parallel to a straight line connecting the pair of Y-axis rotation supports at a frequency equal to or close to the resonance frequency of the second vibration system including the shaft rotation support. And an optical scanner. 7. A plate-shaped mirror for reflecting light, a pair of Y-axis rotation supports positioned on a straight line and supporting both sides of the mirror, and the pair of Y-axis rotation supports are connected. A plate-shaped intermediate supporting portion surrounding the periphery of the mirror in a plane parallel to the mirror; and a piece supporting one side of the intermediate supporting portion positioned parallel to a straight line connecting the pair of Y-axis rotating supports. A pair of X-axis rotating supports that are held beams, a pair of the X-axis rotating supports connected to each other, and a frame that surrounds the periphery of the intermediate support; and a device that applies translational motion to the frame. The mirror has a mass distribution that is asymmetrical with respect to a plane parallel to the mirror, including the pair of Y-axis rotation supports, and the apparatus includes a mirror and the pair of Y-axis rotation supports. At a frequency equal to or near the resonance frequency of the first vibration system configured, Means for generating translational vibration along an X-axis direction parallel to the mirror and orthogonal to a straight line connecting the pair of Y-axis rotation supports, the first vibration system, the intermediate support, and the pair of X-axes Means for generating translational vibration along the Z-axis direction orthogonal to a plane parallel to the mirror at a frequency equal to or close to the resonance frequency of the second vibration system constituted by the rotating support. An optical scanner characterized by: 8. A plate-shaped mirror for reflecting light, a pair of Y-axis rotation supports positioned on a straight line and supporting both sides of the mirror, and the pair of Y-axis rotation supports are connected. A plate-shaped intermediate supporting portion surrounding the periphery of the mirror in a plane parallel to the mirror; and a piece supporting one side of the intermediate supporting portion positioned parallel to a straight line connecting the pair of Y-axis rotating supports. A pair of X-axis rotating supports that are held beams, a pair of the X-axis rotating supports connected to each other, and a frame that surrounds the periphery of the intermediate support; and a device that applies translational motion to the frame. The mirror has a mass distribution that is asymmetrical with respect to a plane parallel to the mirror, including the pair of Y-axis rotation supports, and the intermediate support includes the pair of X-axis rotation supports.
The apparatus has a mass distribution that is asymmetrical with respect to a plane parallel to the intermediate support, and the apparatus has the same resonance frequency as a first vibration system configured by the mirror and the pair of Y-axis rotating supports. Means for generating translational vibration at an approximate frequency along an X-axis direction parallel to the mirror and orthogonal to a straight line connecting the pair of Y-axis rotating supports, the first vibration system and the intermediate support portion; At a frequency that is the same as or near the resonance frequency of the second vibration system constituted by the pair of X-axis rotation supports and the Y-axis direction parallel to a straight line connecting the pair of Y-axis rotation supports. Means for generating translational vibration. 9. The means for generating translational vibration along the X-axis direction and the means for generating translational vibration along the Z-axis direction each comprise a piezoelectric actuator or an electromagnetic actuator. 8. The optical scanner according to claim 5, wherein the drive signal is a signal generated by generating a periodic electric signal and adjusting the amplitude and phase of the periodic electric signal. 10. The means for generating translational vibration along the X-axis direction and the means for generating translational vibration along the Y-axis direction are each composed of a piezoelectric actuator or an electromagnetic actuator. 9. The optical scanner according to claim 6, wherein the drive signal generates a periodic electric signal and adjusts the amplitude and phase of the periodic electric signal.