JP2001359287A - Surface acoustic wave optical element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface acoustic wave optical element which ensures higher energy efficiency. SOLUTION: A generator 12 for generating surface acoustic wave, a transducer 13 and a reflector 15 are formed on a piezoelectric film 11a of a substrate, while a transducer 14 and a reflector 16 are formed on a piezoelectric film 11b. An AC voltage of E1=E0sinωt is applied to a comb-type electrode 12a, while an AC voltage of E2=E0cosωt to a comb-type electrode 12b, forming the generator 12 in order to excite the substrate 11. Thereby, the unidirectional surface acoustic wave W, traveling in the direction of arrow mark a (right side of the figure), is generated. The surface acoustic wave W traveling in the direction of the arrow mark a is converted mechanically and electrically by the transducer 14, energy of such waves is collected as the electrical vibration, it is then circulated to the transducer 13 to re-excite the substrate 11. Optical elements (moving bodies) such as a lens, a polarizer or the like arranged in the space 17 on the substrate 11 can be moved with the surface acoustic wave generated on the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface acoustic wave optical element used in the field of optoelectronics, and more particularly to a surface acoustic wave optical element and a method and apparatus for controlling light using the optical element. .

[0002]

2. Description of the Related Art Conventionally, there has been known a device which employs a means such as blowing hot air from an air conditioner in a vehicle in order to remove water droplets and fogging on a windshield or a side mirror of a vehicle or the like. For a rear window glass of a vehicle or the like, a heating wire is attached to the rear window glass, which is energized and heated to remove fogging.

Some recent cameras have a built-in camera shake correction mechanism. The camera shake correction mechanism moves a correction optical element relative to another optical element such as a lens to reduce image shake. What corrects is known.

[0004] As a means for removing water droplets and fogging on a windshield or a side mirror of a vehicle or the like or for driving a correction optical element of a camera shake correction mechanism, a device using a surface acoustic wave has been proposed.

Several methods have been proposed for exciting surface acoustic waves. For example, JP-A-5-262204
Japanese Patent Application Laid-Open Publication No. H11-157, discloses a device that transmits vibration of an ultrasonic transducer to a windshield of a vehicle via a vibration transmission member. Japanese Patent Application Laid-Open No. 9-313543 discloses a device in which a silicon dioxide film is formed on the surface of glass, a comb-shaped electrode is provided thereon, and surface acoustic waves are excited.

In such a driving device utilizing surface acoustic waves, the vibration energy of the surface acoustic waves traveling on the substrate is converted into heat energy at the end of the substrate and is radiated, resulting in poor energy efficiency. It was.

As a countermeasure against this, it is conceivable to arrange a reflector at the end of the substrate and reflect the surface acoustic wave that has been traveling. However, if the surface acoustic wave is reflected at the end of the substrate, the surface acoustic wave becomes It becomes a standing wave and cannot drive the moving body on the substrate by the surface acoustic wave. In order to drive the moving body, the surface acoustic wave must be a traveling wave traveling on the substrate.

[0008]

As described above, in a driving apparatus utilizing surface acoustic waves, it is necessary to excite a traveling surface acoustic wave on a substrate. At the edge of the substrate, the vibration energy is converted to heat energy and not only wasted, but also the substrate is heated when the vibration energy is converted to heat energy.
For this reason, for example, when glass is used as the substrate, not only the light transmission properties and the light reflection properties of the glass change, but also the glass serving as the substrate has inconveniences such as cracking. SUMMARY OF THE INVENTION It is an object of the present invention to solve various problems of a driving device using surface acoustic waves.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the present invention is directed to a substrate for transmitting or reflecting light, a piezoelectric film provided on the substrate, and a piezoelectric film. A surface acoustic wave generating electrode provided on the substrate, and applying a AC voltage to the energy returning type surface acoustic wave generating electrode to generate a surface acoustic wave on the substrate. An optical element.

The substrate may be formed integrally with the piezoelectric film.

The energy return type surface acoustic wave generating electrode includes an electromechanical conversion electrode for converting an applied AC voltage into a surface acoustic wave, and an AC voltage by receiving a surface acoustic wave traveling on a substrate. A conversion electrode for electromechanical conversion,
Energy is returned by applying an AC voltage converted by the electromechanical conversion electrode to the electromechanical conversion electrode in the same phase.

The surface acoustic wave optical element removes foreign substances adhering to the substrate by means of the surface acoustic wave generated on the substrate, thereby ensuring transmission or reflection of light.
In this case, the foreign matter may be a water droplet.

Further, the surface acoustic wave optical element may include a moving element that is frictionally coupled to the substrate and moves on the substrate by a surface acoustic wave generated on the substrate.

In this case, the moving element can be an optical element for controlling light incident on the substrate.

The optical element may be a lens for controlling the direction of transmission or reflection of light incident on the substrate. Further, the optical element may be a polarizing element that controls a polarization direction of light incident on the substrate.

Further, the optical element may be an optical element incorporated in a photographing lens with camera shake correction.

[0017]

Embodiments of the present invention will be described below. First, the basic configuration of the energy recirculation type surface acoustic wave motor will be described. FIG. 1 is a front view showing a basic configuration of an energy recirculation type surface acoustic wave motor 10 according to the first embodiment. The energy-reflux surface acoustic wave motor of this configuration occupies a large electrode space on the substrate, but can change the traveling direction of the generated surface acoustic wave by giving a phase difference to the AC voltage applied to the drive electrode. it can.

In FIG. 1, reference numeral 11 denotes a substrate, which is a glass plate. Piezoelectric films 11a and 11b made of a piezoelectric material are formed at predetermined intervals in an electrode forming portion. As the material of the piezoelectric film Li Nb O _3,
Alternatively, silicon dioxide or the like can be used.

On the piezoelectric film 11a on the substrate 11, a generator 12 for generating a surface acoustic wave and a generator 1
A first transducer 13 is formed on the left side of FIG. 2 (in FIG. 1), and a first reflector 15 is formed on the left side of the first transducer 13. Also, on the piezoelectric film 11b on the substrate 11,
A second transducer 14 and a second reflector 16 are formed on the right side thereof (in FIG. 1). In addition, 1
Reference numeral 7 denotes a space in which a moving body moved by a surface acoustic wave generated on the substrate 11 is arranged.

The generator 12 includes a first comb-shaped electrode 12a and a second comb-shaped electrode 12b, which are electromechanical conversion electrodes arranged at a distance of 1/4 of the wavelength λ of the generated surface acoustic wave.
It is composed of

The first transducer 13 and the second transducer 14 are conversion electrodes for converting input electric vibration into mechanical vibration and outputting the same, and converting input mechanical vibration into electric vibration and outputting the same. .

The first comb-shaped electrode 12a receives E from the power source 18.
1 = E0 sinωt, the power supply 1 is connected to the second comb-shaped electrode 12b.
By applying an AC voltage of E2 = E0cosωt from 9 to 9, the substrate 11 is excited, and a unidirectional surface acoustic wave W traveling in the direction of arrow a (rightward in FIG. 1) can be generated.

The surface acoustic wave W traveling on the substrate 11 in the direction of arrow a is electromechanically converted by the second transducer 14, and energy is recovered as electric vibration. The collected electric energy is returned to the first transducer 13 to be electromechanically converted, and excites the substrate 11 again.

From the first transducer 13, FIG.
Surface acoustic waves are radiated to both left and right sides, but the surface acoustic waves radiated to the left side in FIG. 1 are reflected by the first reflector 15, so that the surface acoustic waves that excite the substrate 11 are represented by arrows a
Only the surface acoustic wave traveling in the direction becomes.

In this way, the surface acoustic wave traveling on the substrate 11 in the direction of arrow a is collected at the right end of the substrate 11 in FIG.
The substrate 11 is again excited as a surface acoustic wave traveling in the right direction from the left end of the substrate 11, but the phase of the surface acoustic wave traveling in the direction of arrow a emitted from the first transducer 13 is the same as that of the arrow a emitted from the generator 12. Since the phase of the surface acoustic wave traveling in the direction is the same as that of the surface acoustic wave, the amplitude of the surface acoustic wave increases.

Note that the first transducer 13 and the second
Is a conversion electrode that converts electric vibration into mechanical vibration and vice versa.

The phase of the AC voltage applied to the first comb-shaped electrode 12a and the second comb-shaped electrode 12b is adjusted, and the unidirectional surface acoustic wave W traveling in the direction opposite to the arrow a (to the left in FIG. 1). Is generated, the surface acoustic wave W is electromechanically converted by the first transducer 13 and collected, and the collected electric energy is returned to the second transducer 14 to be electromechanically converted and the substrate 11 is again subjected to electromechanical conversion. To excite. At this time, the surface acoustic wave radiated to the right in FIG.
The surface acoustic wave reflected by the second reflector 16 is represented by an arrow a
Only the surface acoustic waves traveling in the opposite direction (to the left in FIG. 1).

FIG. 2 is a front view showing a basic configuration of an energy recirculation type surface acoustic wave motor 20 according to a second embodiment of the present invention. In the energy recirculation type surface acoustic wave motor having this configuration, the electrode space occupying the substrate is small, but the traveling direction of the generated surface acoustic wave is predetermined.

An energy recirculation type surface acoustic wave motor 20 according to the second embodiment is the same as the surface acoustic wave motor 10 according to the first embodiment shown in FIG. It is.

In FIG. 2, reference numeral 21 denotes a substrate, here a glass plate is used, and piezoelectric films 21a and 21b made of a piezoelectric material are formed at predetermined intervals on an electrode forming portion thereof. As the material of the piezoelectric film can be used Li Nb O _3, or silicon dioxide or the like.

The first transducer 22 and the first reflector 24 are formed on the piezoelectric film 21a of the substrate 21, and the second transducer 23 and the second reflector 25 are formed on the piezoelectric film 21b. Is formed. Also, 2
Reference numeral 6 denotes a power supply circuit, and 27 denotes an electric coupler. Reference numeral 28 denotes a space in which a moving body moved by a surface acoustic wave generated on the substrate 21 is arranged.

The first transducer 22 and the second transducer 23 are conversion electrodes for converting input electric vibration into mechanical vibration and outputting the same, and converting the input mechanical vibration into electric vibration and outputting the same. .

The AC voltage output from the power supply circuit 26 is applied to the first transducer 22 through the electric coupler 27, and excites the substrate 21 to move in the direction of arrow a (to the right in FIG. 2). Is generated. At this time, surface acoustic waves are radiated from the first transducer 22 to the left and right sides in FIG. 2, but the surface acoustic waves radiated to the left side in FIG. 2 are reflected by the first reflector 24, The surface acoustic waves that excite the substrate 21 are only surface acoustic waves that travel in the direction of arrow a.

The surface acoustic wave W traveling on the substrate 21 in the direction of arrow a is electromechanically converted by the second transducer 23, and energy is recovered as electric vibration. The recovered electric energy is input to the electric coupler 27, where it is coupled in phase with the AC voltage output from the power supply circuit 26, and an increased AC voltage is output and returned to the first transducer 22. Then, the substrate 21 is excited again.

Also in this case, the output of the electric coupler 27 is
, It is possible to generate a unidirectional surface acoustic wave W that travels in the direction opposite to the arrow a (to the left in FIG. 2). At this time, surface acoustic waves are radiated from the second transducer 23 to both left and right sides in FIG. 2, but the surface acoustic waves radiated to the right side in FIG. 2 are reflected by the second reflector 25 and Are only surface acoustic waves that travel in the direction opposite to the arrow a.

As described above, in the energy recirculation type surface acoustic wave motor, the vibration energy is collected at the end of the substrate.
Since the substrate is used again to excite the substrate, the generation of heat can be suppressed and the surface acoustic wave can be generated efficiently.

The surface acoustic wave motor 10 shown in FIG. 1 has a space 17 and the surface acoustic wave motor 20 shown in FIG.
In FIG. 1, when the moving object is arranged in a space indicated by reference numeral 28, the surface acoustic wave motor 10 shown in FIG.
The moving body is moved by the traveling wave of the surface acoustic wave between the electrode 12a and the second transducer 14, and between the first transducer 22 and the second transducer 23 in the surface acoustic wave motor 20 shown in FIG. be able to.

When the moving body is a solid, the moving body moves in the direction opposite to the traveling direction of the wave due to the backward elliptical motion of the wave front of the surface acoustic wave. When the moving body is a liquid, the moving body moves in the traveling direction of the wave.

FIG. 3 shows the surface acoustic wave motor 10 shown in FIG.
FIG. 2 is a front view showing a configuration of an XY plane drive type surface acoustic wave motor 30 in which two sets of the above electrode groups are arranged so as to intersect on a substrate. In FIG. 3, on the electrode forming portion on a substrate 31 made of a glass plate, piezoelectric films 31a and 31 made of a piezoelectric material are provided.
b, 31c, and 31d are formed. As the material of the piezoelectric film can be used Li Nb O _3, or silicon dioxide or the like.

On the piezoelectric film 31a, the first reflector 35, the first transducer 33, and the one-quarter wavelength λ of the generated surface acoustic wave are arranged from left to right in the X-axis direction. First comb electrode 32a and second comb electrode 32
and a second transducer 34 and a second transducer 34 from left to right in the X-axis direction on the piezoelectric film 31b with a space 40 in which the moving body is disposed separated from the generator 32. A reflector 36 is formed.

Further, on the piezoelectric film 31c, the first reflector 45, the first transducer 43, and a quarter of the wavelength λ of the generated surface acoustic wave are disposed from the bottom in the Y-axis direction. A generator 42 composed of the first comb-shaped electrode 42a and the second comb-shaped electrode 42b is formed, and furthermore, the space 40 where the moving body is arranged is separated by a space above the piezoelectric film 31d in the Y-axis direction. From above, a second transducer 44 and a second reflector 46 are formed.

The first reflectors 35 and 45, the first transducers 33 and 43, and the generators 32 and 4
2, the second transducers 34 and 44, and the second reflectors 36 and 46 are respectively the first reflector 15, the first transducer 13, the generator 12, and the second transducer 14 of the surface acoustic wave motor 10 shown in FIG. , The second reflector 16, detailed description of the configuration and operation will be omitted.

According to such an electrode arrangement, a surface acoustic wave can be generated on the substrate 31 independently in the X-axis direction and the Y-axis direction. Can be freely moved in a plane.

In the surface acoustic wave motor described with reference to FIGS. 1 to 3, the electrode group on the substrate is enlarged for the sake of explanation, and does not indicate the actual size.

Also, in the surface acoustic wave motor described with reference to FIGS. 1 to 3, the description has been made assuming that the piezoelectric film is formed on the substrate. There is no need to form separately.

Next, a description will be given of a first embodiment of a vibration-proof optical device which can be used for camera shake correction and the like to which the XY plane drive type surface acoustic wave motor shown in FIG. 3 is applied.

FIG. 4 is an exploded perspective view showing the structure of the anti-vibration optical device 50, and FIG. 5 is a sectional view thereof. 4 and 5, reference numeral 51 denotes a glass substrate, 57 denotes a correction lens, 56 denotes a lens frame, and the lens frame 56 is made of a magnetic material such as iron. On the back side of the glass substrate 51, a ring-shaped permanent magnet 58 for attracting the lens frame 56 of the correction lens 57 is arranged,
The correction lens 57 is movably held on the surface of the glass substrate 51.

The lens frame 56 and the correction lens 57 held thereon correspond to the moving body of the surface acoustic wave motor having the structure shown in FIG. In FIG. 5, reference numeral 59a denotes a lens disposed in front of the correction lens 57, and reference numeral 59b denotes a lens disposed behind the correction lens 57.

On the glass substrate 51, a piezoelectric film is formed at a portion where an electrode group described below is formed. On the piezoelectric film, a first electrode group 52 and a second electrode group are formed in the X-axis direction. 5
3 are arranged, and a third electrode group 54 and a fourth electrode group 55 are formed in the Y-axis direction.

The first electrode group 52 has the same structure as the first reflector 35, the first transducer 33, and the generator 32 of the surface acoustic wave motor having the structure shown in FIG. , A second transducer 34 and a second reflector 36 shown in FIG.

The third electrode group 54 has the same configuration as the first reflector 45, the first transducer 43, and the generator 42 of the surface acoustic wave motor having the configuration shown in FIG. Reference numeral 55 denotes an electrode group having the same configuration as the second transducer 44 and the second reflector 46 shown in FIG. Therefore, the details of the configuration and operation of the surface acoustic wave motor will be described with reference to FIG. 3, and the detailed description will be omitted.

In the above configuration, the correction lens 57 can be moved in the X-axis direction by driving the first electrode group 52 and the second electrode group 53 to generate a surface acoustic wave traveling in the X-axis direction. it can. The third electrode group 54 and the fourth
By driving the electrode group 55 to generate a surface acoustic wave traveling in the Y-axis direction, the correction lens 57 can be moved in the Y-axis direction.

According to the above configuration, the first lens group to the fourth electrode group are appropriately driven on the basis of the direction and magnitude of the detected camera shake, so that the correction lens 57 is moved to the X direction of the glass substrate 51.
It can be moved to any correction position on the Y plane to correct the image blur on the image plane.

The first to fourth electrode groups are also formed at corresponding positions on the back side of the glass substrate 51 so that the glass substrate 51 is driven from both the front and back surfaces to generate surface acoustic waves. You can also.

The anti-vibration optical apparatus described above uses the XY plane drive type surface acoustic wave motor shown in FIG. 3 in which the surface acoustic wave motors having the structure shown in FIG.
An XY plane drive type surface acoustic wave motor in which surface acoustic wave motors having the configuration shown in FIG. 2 are arranged to cross each other may be used.

Next, a second embodiment of the anti-vibration optical device will be described. The anti-vibration optical device according to the second embodiment also employs the XY plane drive type surface acoustic wave motor shown in FIG. In the anti-vibration optical device of the second embodiment, a spring is used in place of the permanent magnet for holding means of the correction lens, and the other points are the same as those of the first embodiment. The same members have the same reference characters allotted, and detailed description thereof will not be repeated.

FIG. 6 is an exploded perspective view showing the structure of the anti-vibration optical device 60, and FIG. 7 is a sectional view thereof. 6 and 7, 51 is a glass substrate, 57 is a correction lens, 56 is a lens frame, 62, 63, and 64 are springs, and one end of the spring is fixed to a frame 61 disposed in front of the correction lens 57, At the other end of the spring, spherical or other suitable contacts 62a, 63a, 64a are attached.

These contacts press the lens frame 56 against the glass substrate 51 so as not to hinder the free movement of the lens frame 56 and the correction lens 57 held by the lens frame 56 on the XY plane of the glass substrate 51. Holding.

The lens frame 56 and the correction lens 57 held thereon correspond to the moving body of the surface acoustic wave motor having the structure shown in FIG. In FIG. 7, reference numeral 59a denotes a lens disposed in front of the correction lens 57, and reference numeral 59b denotes a lens disposed behind the correction lens 57.

On the glass substrate 51, a piezoelectric film is formed on a portion where an electrode group is formed, similarly to the vibration-proof optical device of the first embodiment described above, and an X-axis is formed on the piezoelectric film. A first electrode group 52 and a second electrode group 53 are arranged in the direction, and a third electrode group 54 and a fourth electrode group 55 are formed in the Y-axis direction.

The first electrode group 52 has the same configuration as the first reflector 35, the first transducer 33, and the generator 32 of the surface acoustic wave motor having the configuration shown in FIG. , A second transducer 34 and a second reflector 36 shown in FIG.

The third electrode group 54 has the same structure as the first reflector 45, the first transducer 43, and the generator 42 of the surface acoustic wave motor having the structure shown in FIG. Reference numeral 55 denotes an electrode group having the same configuration as the second transducer 44 and the second reflector 46 shown in FIG.

In the above arrangement, the correction lens 57 can be moved in the X-axis direction by driving the first electrode group 52 and the second electrode group 53 to generate a surface acoustic wave traveling in the X-axis direction. it can. The third electrode group 54 and the fourth
By driving the electrode group 55 to generate a surface acoustic wave traveling in the Y-axis direction, the correction lens 57 can be moved in the Y-axis direction. Thus, the correction lens 57 can be moved to an arbitrary position on the XY plane of the glass substrate 51.

According to the above arrangement, the first lens group to the fourth electrode group are appropriately driven on the basis of the direction and magnitude of the detected camera shake, so that the correction lens 57
It can be moved to any correction position on the Y plane to correct camera shake.

By forming the first to fourth electrode groups also at the corresponding positions on the back side of the glass substrate 51, it is possible to drive the glass substrate 51 from both front and back surfaces to generate surface acoustic waves. You can also.

The anti-vibration optical device described above uses the XY plane drive type surface acoustic wave motor shown in FIG. 3 in which the surface acoustic wave motors having the structure shown in FIG.
An XY plane drive type surface acoustic wave motor in which surface acoustic wave motors having the configuration shown in FIG. 2 are arranged to cross each other may be used.

Next, a description will be given of a polarizing device configured to rotate a polarizing plate using an XY plane drive type surface acoustic wave motor. This polarizing device rotates a polarizing plate using the XY plane drive type surface acoustic wave motor shown in FIG. 3, and FIG. 8 is a perspective view showing the configuration of a polarizing device 80.
FIG. 9 is a front view thereof, and FIG. 10 is a sectional view thereof.

8 to 10, reference numeral 81 denotes a glass substrate, 87 denotes a polarizing plate, and 86 denotes a frame for holding the polarizing plate 87.
The frame 86 is made of a magnetic material such as iron. Glass substrate 81
A ring-shaped permanent magnet 88 for attracting a frame 86 to which a polarizing plate 87 is fixed is disposed on the back side of the polarizing plate 87, and the polarizing plate 87 is rotatably held on the surface of the glass substrate 81.

Since an electrode group is formed on the glass substrate 81 so as to surround the polarizing plate 87 as described later, the piezoelectric films 81a, 81b, 81c, 8
1d is formed.

An electrode group is formed on the piezoelectric films 81a, 81b, 81c, 81d so as to surround the polarizing plate 87.
That is, in FIG. 9, a first electrode group 82 and a second electrode group 83 are formed on the piezoelectric films 81a and 81b, and a third electrode group 84 and a second electrode group are formed on the piezoelectric films 81c and 81d. Groups 85 are formed.

The first electrode group 82 is an electrode group having the same configuration as the first reflector 35, the first transducer 33, and the generator 32 of the surface acoustic wave motor having the configuration shown in FIG. , A second transducer 34 and a second reflector 36 shown in FIG.

The third electrode group 84 has the same configuration as the first reflector 45, the first transducer 43, and the generator 42 of the surface acoustic wave motor having the configuration shown in FIG. Reference numeral 85 denotes an electrode group having the same configuration as the second transducer 44 and the second reflector 46 shown in FIG.

The details of the configuration and operation of the surface acoustic wave motor will be described with reference to FIG. 3, and a detailed description thereof will be omitted. However, by driving the first electrode group 82 and the second electrode group 83, In FIG. 9, a surface acoustic wave traveling in the direction of arrow a (from top to bottom) is generated on the left side of the glass substrate 81, and the third electrode group 84 and the fourth electrode group 85 are driven. When a surface acoustic wave traveling in the direction of arrow b (from bottom to top) is generated on the right side of 81, the left side of the polarizing plate 87 moves from bottom to top and the right side of the polarizing plate 87 moves from top to bottom ( In the case where the moving body is a solid, it moves in the direction opposite to the traveling direction of the wave due to the backward elliptical motion of the wave front of the surface acoustic wave traveling wave), and the polarizing plate 87 can be rotated clockwise.

When the glass substrate 81 is also made of a plate having polarization characteristics, the amount of transmitted light can be adjusted by rotating the polarizing plate 87.

In the polarizing device described above, two sets of surface acoustic wave motors having the structure shown in FIG. 1 are used. However, it is needless to say that two sets of surface acoustic wave motors having the structure shown in FIG. 2 can be used. No.

Next, a description will be given of a water droplet removing device 90 which uses the surface acoustic wave motor having the structure shown in FIG. 1 to remove water droplets and fogging attached to a windshield of an automobile.

FIG. 11 is a perspective view showing the configuration of a water droplet removing device 90 mounted on a windshield of an automobile, in which a surface acoustic wave motor having the configuration shown in FIG.

That is, the piezoelectric film 91a is formed along the upper side of the windshield 91, the piezoelectric film 91b is formed along the lower side of the windshield 91, and the first electrode group 92 is formed on the piezoelectric film 91a. A second electrode group 93 is formed thereon.

The first electrode group 92 has the same configuration as the first reflector 35, the first transducer 33, and the generator 32 of the surface acoustic wave motor having the configuration shown in FIG. , The second transducer 34 and the second reflector 36 shown in FIG. 3, and a plurality of first electrode groups 92 and second electrode groups 93 required according to the width of the windshield 91. Arrange them side by side.

The details of the configuration and operation of the surface acoustic wave motor will be described with reference to FIG. 3, and the detailed description is omitted here. The first electrode group 92 and the second electrode group 93 are driven, In FIG. 11, when a surface acoustic wave traveling from the upper side to the lower side of the windshield 91 is generated, water droplets and fogging adhering on the windshield 91 move downward by the traveling wave of the surface acoustic wave, and the adhering water droplets and Fogging can be removed.

In the water droplet removing apparatus described above, the surface acoustic wave motor having the configuration shown in FIG. 1 is used. However, it is needless to say that the surface dropping motor can be configured using the surface acoustic wave motor having the configuration shown in FIG.

[0082]

As described above in detail, the surface acoustic wave optical element according to the present invention recovers the surface acoustic wave energy that has advanced to the end of the surface acoustic wave element, and uses the recovered energy to generate the surface acoustic wave element. Since re-excitation can be performed efficiently, energy can be efficiently recovered and re-excited, and a surface acoustic wave optical element with high energy efficiency can be provided.

[Brief description of the drawings]

FIG. 1 is a front view showing a basic configuration of an energy recirculation type surface acoustic wave motor according to a first embodiment.

FIG. 2 is a front view showing a basic configuration of an energy recirculation type surface acoustic wave motor according to a second embodiment.

FIG. 3 is a front view showing a configuration of an XY plane drive type surface acoustic wave motor 30 in which electrodes of the surface acoustic wave motor 10 shown in FIG.

FIG. 4 is a perspective view of the image stabilizing optical apparatus according to the first embodiment.

FIG. 5 is a cross-sectional view of the image stabilizing optical device shown in FIG.

FIG. 6 is a perspective view of an image stabilizing optical device according to a second embodiment.

FIG. 7 is a sectional view of the image stabilizing optical device shown in FIG. 6;

FIG. 8 is a perspective view of a polarizing device using a surface acoustic wave motor for rotating a polarizing plate.

FIG. 9 is a front view of the polarization device shown in FIG. 8;

FIG. 10 is a sectional view of the polarizing device shown in FIG. 8;

FIG. 11 is a perspective view showing a configuration of a water droplet removing device mounted on a windshield of an automobile.

[Explanation of symbols]

 Reference Signs List 10 surface acoustic wave motor 11 substrate 11a, 11b piezoelectric film 12 generator 12a first comb-shaped electrode 12b second comb-shaped electrode 13 first transducer 14 second transducer 15 first reflector 16 second reflector 17 space (moving) 20 Surface acoustic wave motor 21 Substrate 21a, 21b Piezoelectric film 22 First transducer 23 Second transducer 24 First reflector 25 Second reflector 26 Power supply circuit 27 Electric coupler 28 Space (moving body) 30) Surface acoustic wave motor 31 Substrate 31a, 31b, 31c, 31d Piezoelectric film 32, 42 Generator 33, 43 First transducer 34, 44 Second transducer 35, 45 First reflector 36, 46 First 2 reflation 40 40 Space (where a moving body is disposed) 50 Anti-vibration optical device 51 Glass substrate 52 First electrode group 53 Second electrode group 54 Third electrode group 55 Fourth electrode group 56 Lens frame 57 Correction lens 58 Permanent magnet 60 Vibration optical device 62, 63, 64 Spring 80 Polarizing device 81 Glass substrate 81a, 81b, 81c, 81d Piezoelectric film 82 First electrode group 83 Second electrode group 84 Third electrode group 85 Fourth electrode group 86 Frame 87 Polarizing plate 88 Permanent magnet 91 Windshield 91a, 91b Piezoelectric film 92 First electrode group 93 Second electrode group

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H01L 41/09 H01L 41/08 U F term (Reference) 2H041 AA12 AA22 AB24 AB30 AC08 AZ01 3D025 AA01 AC18 AD02 AD04 5D107 AA03 BB06 BB11 CC02 CC06 FF02 FF07 5H680 AA08 AA19 BB03 BB13 BC01 CC08 DD01 DD23 DD39 DD53 DD76 DD82 FF33

Claims (10)

[Claims] A substrate that transmits or reflects light; a piezoelectric film provided on the substrate; and an energy return type surface acoustic wave generation electrode provided on the piezoelectric film; A surface acoustic wave optical element characterized in that a surface acoustic wave is generated on a substrate by applying an AC voltage to a surface wave generating electrode. 2. The surface acoustic wave optical element according to claim 1, wherein said substrate is formed integrally with a piezoelectric film. 3. The surface acoustic wave generating electrode according to claim 1, further comprising: an electromechanical conversion electrode for converting an applied AC voltage into a surface acoustic wave; and an AC voltage after receiving the surface acoustic wave traveling on the substrate. 2. The elasticity according to claim 1, further comprising: an electromechanical conversion electrode for converting, and applying an AC voltage converted by the electromechanical conversion electrode to the electromechanical conversion electrode in the same phase to perform energy recirculation. Surface wave optical element. 4. The surface acoustic wave optical element according to claim 1, wherein the surface acoustic wave generated on the substrate removes foreign substances adhering to the substrate to secure transmission or reflection of light. Surface acoustic wave optical element. 5. The surface acoustic wave optical element according to claim 4, wherein said foreign matter is a water droplet. 6. The surface acoustic wave optical element according to claim 1, further comprising a moving element that is frictionally coupled to the substrate and moves on the substrate by a surface acoustic wave generated on the substrate.
The surface acoustic wave optical element according to any one of the preceding claims. 7. The surface acoustic wave optical element according to claim 6, wherein the movable element is an optical element that controls light incident on the substrate. 8. The surface acoustic wave optical element according to claim 7, wherein the optical element is a lens for controlling a transmission or reflection direction of light incident on the substrate. 9. The surface acoustic wave optical element according to claim 7, wherein the optical element is a polarizing element that controls a polarization direction of light incident on the substrate. 10. The surface acoustic wave optical element according to claim 7, wherein the optical element is an optical element incorporated in a photographing lens with camera shake correction.