JPH0954264A - Optical scanner, distance measurng device and photosensor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact and inexpensive optical scanner which does not require the complicated adjustment of an optical axis, freely adjusts a scanning range and realizes two-dimensional optical scanning. SOLUTION: A turning block 3 is supported by a rotation driving part 1 such as a pulse step motor, etc. In the block 3, the lower end of a movable plate 4 which can be bent and deformed is fixed on a fixed plate 6, a permanent magnet 8 is attached to the back surface of the plate 4, and the fixed plate 6 is provided with a coil 9. A light reflection surface 7 is formed on the front surface of the plate 4. By turning the block 3 by the driving part 1 or exciting the coil 9, the plate 4 is turned in two directions and stands still at an optional angle. A rotational angle by the driving part 1 is detected by a rotational driving angle detection means 13 such as a rotary encoder, etc., and the rotational angle in the bending direction of the plate 4 is detected by a bending angle detection means 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning device, and more particularly to an optical scanning device capable of two-dimensional scanning with a light beam. Further, the present invention relates to a distance measuring device and an optical sensor device using the optical scanning device.

[0002]

2. Description of the Related Art There are two conventional two-dimensional optical scanning devices P.
There is one using two galvanometer mirrors 71 and 72 (for example, Japanese Patent Laid-Open No. 2-232617). This is shown in FIG.
As shown in FIG. 4, a first galvanometer mirror 71 rotated by a drive unit 73 such as a motor and a drive unit 7 such as a motor.
The second galvanometer mirror 72 rotated by 4 and the condenser lens 75 are arranged along the optical path of the light beam α. Then, the light beam α emitted from the light source 76 is reflected by the first galvanometer mirror 71 and the second galvanometer mirror 72 and then condensed by the condenser lens 75. By rotating 72, the light beam α can be scanned two-dimensionally.

However, in such a two-dimensional optical scanning device P, since the light beam α scanned one-dimensionally by the first galvano mirror 71 is received by the second galvano mirror 72 and reflected, A second galvano mirror 72 having a size capable of covering the scanning range of the light beam α by the first galvano mirror 71 is required, and there is a drawback that the second galvano mirror 72 becomes large. Furthermore, two drive units 73 and 74 and two Galvano mirrors 71 and 72
Therefore, it is difficult to reduce the overall size of the optical scanning device P. Also, two galvanometer mirrors 7
It is necessary to align the optical axes of the light sources 1, 72 and the light source 76, and it is troublesome to perform the optical axis alignment work.

As another conventional example (not shown) of the two-dimensional optical scanning device, the mirror on the outer peripheral surface is tilted,
There is a polygon mirror with a tilted axis. In this, the mirror surfaces formed on the outer peripheral surfaces of the polygon mirror are tilted at different angles with respect to the rotation axis, or the axis of the polygon mirror is tilted with respect to the rotation axis.

However, in the optical scanning device of such a system, the scanning range of the light beam is determined by the number of mirror surfaces of the polygon mirror, so that the scanning range of the light beam in the main scanning direction is limited. If an attempt is made to widen the scanning range in the main scanning direction, the number of mirror surfaces of the polygon mirror is reduced, and the number of scanning lines in the sub scanning direction is reduced. Also, in order to increase the number of scanning lines in the sub-scanning direction, it is sufficient to increase the number of mirror surfaces, but if the number of mirror surfaces is increased,
There is a problem that the scanning range in the main scanning direction becomes narrow. Further, in order to widen the scanning range in the main scanning direction and increase the number of scanning lines in the sub scanning direction, it is necessary to increase the diameter of the polygon mirror, which increases the size of the optical scanning device and reduces the manufacturing cost. It had the drawback of being expensive.

Further, FIG. 15 shows another conventional resonance mirror type two-dimensional optical scanning device Q. This is because both ends of the spring arm 81 bent in an asymmetrical shape are connected to the elastic support piece 8.
2 and 83, one end of the bending vibration piece 84 is fixed to one end of the spring arm 81, the mirror 85 is fixed to the other end of the bending vibration piece 84, and the piezoelectric vibration is further applied to one end of the arm 81. Vibration is applied from the child 86. Then, when vibration is applied from the piezoelectric vibrator 86 to the arm 81 and the bending vibration piece 84 and the light beam α emitted from the light source 87 is reflected by the mirror 85, the bending vibration piece 8 is generated.
4 resonates and vibrates, the mirror 85 rotates in a horizontal plane, and the light beam α is horizontally scanned. At the same time, the arm 81 resonates and vibrates, and the mirror 85 rotates in a vertical plane, and the scanning line of the light beam α moves in the vertical direction.

However, in such a resonance mirror type two-dimensional optical scanning device Q, the arm 81 and the bending vibration piece 8 are used.
Since No. 4 was driven by resonance, the scanning speed could not be changed in the horizontal direction or the vertical direction. Further, since the resonance drive is used, it is vulnerable to disturbance vibration, and there is a problem that disturbance vibration causes disturbance in the scanning direction, vibration stop, or fatigue failure.

Further, in any of the two-dimensional optical scanning devices, it is not possible to know the scanning angle of the light beam because it has no means for detecting the emission angle of the light beam.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the drawbacks of the above-mentioned conventional examples, and its object is to eliminate the need for complicated optical axis adjustment and to freely set the scanning range. An object of the present invention is to provide a small and inexpensive optical scanning device that can be adjusted and can scan a light beam in two directions.

Another object of the present invention is to make it possible to detect the scanning angle of a light beam with a simple structure.

Another object of the present invention is to provide an optical scanning device that is resistant to shock.

[0012]

DISCLOSURE OF THE INVENTION In an optical scanning device according to claim 1, a reflection surface for reflecting light, a rotation driving means for rotating the reflection surface, and an angle formed by the reflection surface and a rotation axis of the rotation driving means. Is configured by an angle changing unit that changes by an electromagnetic force such as an electrostatic force or a magnetic force.

The rotation driving means for rotating the reflecting surface is not particularly limited, but for example, a control motor such as a pulse step motor or an air driven rotary actuator can be used. Further, the electromagnetic force for operating the angle changing means is not limited to the electrostatic force or the magnetic force,
The piezoelectric effect of a ferroelectric substance is also included.

The reflecting surface is rotated about the rotation axis of the rotation driving means by the rotation driving means. Further, the reflecting surface is rotated by the angle changing means about an axis in a direction substantially orthogonal to the rotation axis of the rotation driving means. Therefore, the reflecting surface rotates in two directions, and the light beam reflected by this reflecting surface is scanned in two directions.

According to a second aspect of the present invention, in the optical scanning device according to the first aspect, the rotation driving means rotates the angle changing means together with the reflecting surface.

In this embodiment, the rotation driving means rotates the angle changing means around the rotation axis, and the reflecting surface is rotated by the angle changing means around the axis in a direction substantially orthogonal to the rotation axis. Be moved. Therefore, the reflecting surface rotates in two directions, and the light beam reflected by this reflecting surface is scanned in two directions.

According to a third aspect of the present invention, in the optical scanning device according to the first or second aspect, the angle changing means includes a movable plate that can be bent and deformed, and an electromagnetic force such as an electrostatic force or a magnetic force. It is characterized in that the angle formed between the reflecting surface and the rotation axis of the rotation driving means is changed by bending the movable plate caused by the above.

In this embodiment, the reflecting surface can be rotated around an axis in a direction substantially orthogonal to the rotation axis of the rotation driving means by elastically bending and deforming the movable plate by an electromagnetic force.

According to a fourth aspect of the present invention, in the optical scanning device according to the third aspect, the angle changing means arranges a fixed plate and a movable plate so as to face each other. Each of them is provided with a member that interacts with each other by an electromagnetic force such as an electrostatic force or a magnetic force, and a movable plate is provided with a reflecting surface.

In this embodiment, since the reflecting surface is provided on the movable plate, the reflecting surface can be directly rotated by bending and deforming the movable plate.

According to a fifth aspect of the present invention, in the optical scanning device according to the fourth aspect, the fixed plate and the movable plate are partially fixed to each other, and the rotation driving means includes both the fixed plate and the movable plate. The feature is that it is designed to rotate.

In this embodiment, the fixed plate and the movable plate are rotated by the rotation driving means, and the movable plate is bent and deformed, so that the reflecting surface provided on the movable plate is rotated in two directions. The light reflected by is scanned in two directions.

In the optical scanning device according to the first to fifth aspects, since the reflecting surface is rotated by the rotation driving means and the reflecting surface is rotated in different directions by the angle changing means, the reflecting surface is bidirectional. When the light beam is applied to the reflecting surface, the light beam is scanned in two directions.

Further, in this optical scanning device, since one reflecting surface is rotated in two directions by the combination of the rotation driving means and the angle changing means, the optical scanning device can be miniaturized. . Moreover, since there is only one reflecting surface, complicated optical axis adjustment and assembly precision are not required, and the manufacturing cost can be reduced.

Further, the angle changing means forcibly rotates the reflecting surface by the electromagnetic force, and the scanning speed, scanning angle and scanning range of the light beam can be freely adjusted.

According to a sixth aspect of the present invention, in the optical scanning device according to the fourth aspect, a control means for controlling an electromagnetic force such as an electrostatic force or a magnetic force is provided on the back side of the fixed plate. I am trying.

In this embodiment, since the control means is provided on the fixed plate, the optical scanning device including the control means can be downsized. Moreover, since the control means is provided on the back side of the fixed plate, that is, on the side opposite to the surface facing the movable plate, there is no fear that the control means interferes with the deforming operation of the movable plate.

According to a seventh aspect of the present invention, in the optical scanning device according to the fourth aspect, a bending angle detecting means for detecting an angle formed by the reflecting surface and the rotation axis of the rotation driving means is provided. Is characterized by.

According to an eighth aspect of the present invention, in the optical scanning device according to the seventh aspect, the bending angle detecting means is based on an electrostatic capacitance between a fixed plate and a movable plate, and It is characterized in that the angle formed by the rotation axis of the rotation drive means is detected.

According to the eighth aspect of the present invention, when the movable plate is bent and deformed, the electrostatic capacitance between the movable plate and the fixed plate changes, so that the value of the electrostatic capacitance determines the reflection surface and the rotary shaft. You can know the angle.

According to a ninth aspect of the present invention, in the optical scanning device according to the seventh aspect, the bending angle detecting means is based on a value of a strain detecting element such as a strain gauge attached to the movable plate. It is characterized in that an angle formed by the reflection surface and the rotation axis of the rotation driving means is detected.

In this embodiment, it is possible to know the angle formed between the reflecting surface and the rotation axis by detecting the strain of the bent portion of the movable plate by the strain detecting element.

Since the means for detecting the angle formed by the reflecting surface and the rotation axis of the rotation driving means is provided, the bending angle in the deformation direction of the movable plate can be detected. Therefore, the scanning angle of the light beam in the relevant direction can be known. Particularly, in the embodiment of claim 8,
Since the bending angle of the movable plate can be detected based on the electrostatic capacitance between the movable plate and the fixed plate, the bending angle detecting means can be made thin and space-saving.
A three-dimensional optical scanning device can be manufactured. Similarly, in the embodiment of claim 9, since the bending angle of the movable plate can be detected by the strain detecting element such as the strain gauge attached to the movable plate, the bending angle detecting means can be made thin to realize space saving. It is possible to manufacture a small two-dimensional optical scanning device while having the detecting means.

The embodiment as claimed in claim 10 is as claimed in claim 7.
In the optical scanning device described in (1), the angle of the reflecting surface detected by the bending angle detecting means is compared with a target value of the angle, and the angle of the reflecting surface detected by the bending angle detecting means always matches the target value. As described above, the electromagnetic force such as the electrostatic force or the magnetic force is controlled.

In this embodiment, since the angle of the reflecting surface detected by the bending angle detecting means is controlled to match the target value, the rotation angle of the reflecting surface in the bending direction of the movable plate is the target value. Can be controlled to match.
Therefore, the scanning angle of the light beam can be accurately controlled. In addition, since a feedback loop can be formed, the stability of the entire control system is improved, and it becomes stronger against external disturbance such as impact. Further, when this optical scanning device is used as an optical sensor for detecting an object, it is possible to accurately obtain position information of the detected object.

The embodiment according to claim 11 is the embodiment according to claim 4.
In the optical scanning device described in the paragraph 1, the movable plate is formed with a constricted portion for causing bending deformation.

When the movable plate is provided with the constricted portion, the elastically deformable region of the movable plate can be limited, so that the rigidity of the movable plate can be reduced, the force required for bending deformation can be reduced, and the driving force can be reduced. Can be kept small, and power can be saved.

The embodiment described in claim 12 is the embodiment described in claim 4.
In the optical scanning device described in the paragraph 1, the movable plate is made of a metal material having a large fatigue limit such as beryllium copper or phosphor bronze.

If the movable plate is formed of a metal material having a large fatigue limit such as beryllium copper or phosphor bronze, the movable plate will not be broken even if it is repeatedly bent and deformed, and the optical scanning device can be scanned at high speed for a long time. And reliability is improved. Moreover, since the metal movable plate itself serves as an electrode, the number of parts and the number of assembly steps can be reduced, and the manufacturing cost can be reduced.

The embodiment described in claim 13 is the embodiment described in claim 4.
In the optical scanning device described in the paragraph 1, the fixed plate is provided with a stopper for limiting a movable range of the movable plate.

If the movable plate is provided with a stopper that limits the movable range, even if a large force (for example, drop impact force) is applied, the movable plate will not be deformed enough to exceed the breaking limit value, and the movable plate is protected from impacts. The reliability is also improved, and it is possible to use it under vibration (for example, mounting it on an automobile).

An optical scanning device according to a fourteenth aspect of the present invention is a fixed plate, a movable plate which is bendable and deformable so as to face the fixed plate, and electrostatic forces provided on the fixed plate and the movable plate, respectively. Members that interact with each other by electromagnetic force such as magnetic force, control means for controlling this electromagnetic force, a light source provided on the movable plate, and the fixed plate and the movable plate in a direction different from the bending direction of the movable plate. And a rotary drive means for rotating the.

In this optical scanning device, the movable plate is rotated in one direction by the rotation driving means, and the movable plate is bent and deformed in the other direction by the electromagnetic force.
The light source provided on the movable plate rotates in two directions, and the light beam emitted from the light source can be scanned in two directions.

Therefore, even in this optical scanning device, since one light source is rotated in two directions by the rotation driving means and the angle changing means, the optical scanning device can be miniaturized. Moreover, since the light source is provided directly on the movable plate, complicated optical axis adjustment and assembly accuracy are not required,
The manufacturing cost can be reduced. Further, the angle changing means forcibly rotates the reflecting surface by the electromagnetic force, and the scanning speed and scanning range of the light beam can be freely adjusted.

A distance measuring device according to a fifteenth aspect comprises the optical scanning device according to the first aspect for scanning a target with light, and a light receiving means for receiving reflected light from the target. It is characterized in that the distance to the target is measured based on the received light signal.

Since this distance measuring device is equipped with the optical scanning device of the present invention, the distance measuring device capable of two-dimensional optical scanning can be realized in a small size and at low cost. Further, the two-dimensional scanning enables high-density light transmission, and a distance measuring device capable of longer distance measurement can be provided.

An optical sensor device according to a sixteenth aspect is an optical scanning device according to any one of the first to fourteenth aspects for scanning light on an object to be detected, and a light receiving element for detecting the intensity of reflected light from the object to be detected. , A signal processing means for processing an electric signal output from the light receiving element, and the position, shape, and dimension of the detection target,
Or the mark, pattern, code, character, which is the object to be detected,
It is characterized by sensing information such as.

Since the optical sensor device of the present invention is equipped with the optical scanning device of the present invention, it is small and inexpensive, and
An object can be detected in a dimensional detection area (for example, a square or rectangular area). In particular, when used for reading code information such as bar codes, multi-level bar codes, and matrix-shaped two-dimensional bar codes, the code information reading device is small and inexpensive, and can be used even in an environment with disturbance vibration. Can be used.

[0049]

1 is a perspective view showing an optical scanning device A according to an embodiment of the present invention, and FIG. 2 is a side view thereof. The rotary drive unit 1 (rotary drive means) is composed of a control motor such as a stepping motor, and can rotate the rotary shaft 2 reciprocally.
The rotation speed and rotation range of the rotation shaft 2 can be freely changed. A rotating block 3 is supported at the tip of the rotating shaft 2. The rotating block 3 is formed by fixing both sides of the lower end of a movable plate 4 which can be bent and deformed to the lower end of a fixed plate 6 via a spacer 5. A reflecting surface 7 is provided on the front surface of a movable plate 4 supported so as to face the fixed plate 6 with a constant distance d ₀ , and a permanent magnet 8 is attached to the back surface. The reflecting surface 7 may be formed by adhering another member such as a mirror to the movable plate 4, or may be formed by directly vapor-depositing aluminum or the like on the surface of the movable plate 4, or the movable plate 4
The surface of may be mirror-finished.

The angle changing means for bending and deforming the movable plate 4 is composed of a permanent magnet 8 provided on the movable plate 4 and a coil 9 provided on the fixed plate 6. Permanent magnet 8
Are arranged so that the magnetization direction is in the front-back direction of the movable plate 4, and are, for example, the directions shown in FIG. The fixed plate 6 is composed of a circuit board, and the coil 9 for generating a magnetic field is provided on the back surface of the fixed plate 6. Also,
A drive circuit 10 (control means) for exciting the coil 9 and controlling the rotation drive unit 1 is provided on the back surface of the fixed plate 6. An opening 11 is formed in the fixed plate 6 so as to face the inner peripheral surface of the coil 9, and the permanent magnet 8 fixed to the movable plate 4 is partially inserted in the opening 11 and the coil 9. .

The optical scanning device A is arranged so that the light beam α emitted from the light source 12 such as a semiconductor laser element or a light emitting diode (LED) is received by the reflecting surface 7 and reflected.

However, in this optical scanning device A,
When the rotary drive unit 1 is driven, the rotary block 3 is rotated by the rotary shaft 2.
It rotates about the axis a (Z-axis direction) and swings left and right within a predetermined rotation range. At this time, the light beam α reflected by the reflecting surface 7 is scanned in the horizontal direction (p direction) by changing the scanning angle by 2θz when the rotating block 3 rotates by the angle θz. In addition, the rotation drive unit 1 can rotate the rotation block 3 at an arbitrary rotation angle θz and make the rotation block 3 stand still at an arbitrary position.

Further, in this optical scanning device A, when the coil 9 is energized, an NS magnetic field is generated at both ends of the coil 9 according to the right-handed screw law. At this time, when the coil 9 is energized so that the direction of the magnetic field generated in the coil 9 is the same as the magnetization direction of the permanent magnet 8, the permanent magnet 8 and the coil 9 are
Since the opposite sides of the two have opposite polarities, the permanent magnet 8 is drawn into the coil 9. As a result, as shown in FIG. 3A, the movable plate 4 is curved and drawn toward the fixed plate 6. In addition, the direction of the magnetic field generated in the coil 9 depends on the permanent magnet 8
When the coil 9 is energized in a direction opposite to the magnetization direction of, the permanent magnet 8 and the side of the coil 9 facing each other have the same polarity, so that the permanent magnet 8 is repulsed from the coil 9. As a result, as shown in FIG. 3B, the movable plate 4 curves and separates from the fixed plate 6. Therefore, when an alternating current is applied to the coil 9, the magnetic force of the permanent magnet 8 and the coil 9 causes the movable plate 4 to move.
Bends and vibrates. The movable plate 4 that is bending and vibrating is the rotating shaft 2.
When tilted by an angle θx with respect to the axis of, the scanning angle of the light beam α reflected by the reflecting surface 7 changes by 2θx, and the reflecting surface 7
The light beam α reflected by is scanned in the vertical direction (q direction) in FIG. Further, the reflecting surface 7 can be made stationary at an arbitrary angle by passing a constant current in either direction through the coil 9.

Therefore, while rotating the rotary drive unit 1 to rotate the rotary block 3, at the same time, an alternating current is applied to the coil 9 to vibrate the movable plate 4, whereby the light beam reflected by the reflecting surface 7 is reflected. It is possible to scan α in two dimensions. Further, according to the optical scanning device A, by controlling the rotation drive unit 1 and by changing the current value and frequency of the current flowing in the coil 9, the scanning range (2θz) max and the scanning speed in the p direction are obtained. , Q-direction scanning range (2θ
x) max and the scanning speed can be changed.

Further, in this optical scanning device A, the p direction and the q direction are
Any of the directions may be the main scanning direction and any of the directions may be the sub scanning direction. Further, since it is not a resonance type, it can be stopped at an arbitrary position in the p direction and one-dimensionally scanned in the q direction, or it can be made stationary at an arbitrary position in the q direction and one-dimensionally scanned in the p direction. Further, the light beam α can be stopped at any one point within the two-dimensional scanning area.

A rotation drive angle detecting means 13 such as a rotary encoder for detecting the rotation angle θz of the rotation shaft 2 is provided on the lower surface of the rotation drive unit 1, and the axis of the rotation shaft 2 (Z-axis). ) The rotation angle θz of the reflecting surface 7 is detected by the rotation drive angle detection means 13.

Further, the bending angle detecting means 14 for detecting the bending angle θx of the movable plate 4 includes the electrode 15 provided on the movable plate 4.
And an electrode 16 on the fixed plate 6 provided at a position facing the electrode 15 and both electrodes 15, 16
The bending angle θx is detected by measuring the electrostatic capacitance C between them. That is, the capacitance C between the electrodes 15 and 16 is
Area S of electrodes 15 and 16, distance d between electrodes, electrodes 15 and 1
It is expressed by the following equation by the dielectric constant ε between 6 (air). C = εS / d ... When the distance from the fixed end of the movable plate 4 to the electrode 15 is L and the distance between the electrodes at rest (when the coil is not energized) is d ₀ , the electrode when the movable plate 4 is bent The distance d is expressed by the following equation. d = d ₀ + L · tan (θx) Therefore, according to the above and the formula, the detected capacitance C
The bending angle θx can be obtained from

Thus, the rotation angle θz of the reflecting surface 7 and the movable plate 4
If the bending angle θx is detected, the scanning directions 2θz and 2θx of the light beam α at that moment can be obtained.

If the movable plate 4 is formed of a highly conductive metal material such as an aluminum alloy, it is not necessary to separately provide the electrode 15 on the movable plate 4, and the movable plate 4 itself and the electrodes 16 are provided.
The bending angle detecting means 14 can be configured by this, and it is effective in reducing the number of parts and the number of assembling steps. Further, when the movable plate 4 is formed of a metal material having a large fatigue limit such as stainless steel, the movable plate 4 is not broken even when repeatedly bent and deformed, and the reliability is improved. Further, if the movable plate 4 is formed of a metal material having good conductivity and a large fatigue limit, for example, beryllium copper or phosphor bronze, the bending angle detection means 14 can be configured by the movable plate 4 itself and the electrode 16. This has the effect of reducing the number of parts and the number of assembling steps, and at the same time, even if the movable plate 4 is repeatedly bent and deformed, the movable plate 4 is not destroyed and reliability is improved.

Further, a stopper 19 which is sufficiently longer than the distance between the movable plate 4 and the fixed plate 6 is loosely inserted into the through hole 17 of the fixed plate 6 and the through hole 18 of the movable plate 4, and the stopper 1
At both ends of 9 are retaining portions 2 that are larger than the through holes 17 and 18.
0 is provided. Therefore, the movable plate 4 is limited in its movable range to the side opposite to the fixed plate 6 by the stopper 19, and the movable range of the movable plate 4 to the fixed plate 6 side is limited by the fixed plate 6. The plate 4 is prevented from being largely bent and causing permanent strain or breakage. Therefore, the impact resistance of the movable plate 4 is improved, and even if a drop impact force is applied, the movable plate 4 will not be deformed enough to exceed the breaking limit value. It is also possible to use it while receiving vibration from the surroundings (for example, when it is mounted on an automobile).

Although the coil 9 is provided on the back surface of the fixed plate 6 in FIG. 1, it may be provided on the front surface of the fixed plate 6. In addition, the electrode 1 for detecting the bending angle of the movable plate 4
Although 5 and 16 are arranged below the permanent magnet 8 in FIG. 1, they may be arranged on both sides of the permanent magnet 8.

FIG. 4A is a front view showing the movable plate 4 having a different shape. In the present embodiment, the bending portion 21 (constricted portion) that is elastically deformed during bending deformation is provided by making the central portion of the movable plate 4 thinner than both end portions. That is, as shown in the side view at the time of bending deformation shown in FIG. 4B, the movable plate 4 is not deformed in the wide regions of both ends (the reflection surface 7 is provided in the region), and the central portion is not deformed. It is elastically deformed only at the bent and deformed portion 21. As a result of providing the bending deformation portion 21 limited in this way, the movable plate 4
Since the spring rigidity can be reduced and the force required for bending deformation can be reduced, the permanent magnet 8 and the coil 9 can be downsized, and power consumption can be further reduced. Further, the roots and the corner portions 22 of the tip end of the bending deformation portion 21 are rounded to reduce stress concentration and prevent the bending deformation portion 21 from being damaged.

FIG. 5A shows a movable plate 4 having a different shape.
FIG. In this embodiment, the bending deformation portion 2 is formed from the root to the tip so that the stress generated in the bending deformation portion 21 of the movable plate 4 due to the bending deformation becomes substantially equal.
It is a taper of 1 (isostress beam). As a result, stress concentration at the root of the bending deformation portion 21 can be reduced, and it is difficult to break and reliability is improved.

FIG. 6 is a perspective view showing an optical scanning device B according to another embodiment of the present invention. In this optical scanning device B, as the bending angle detecting means 14 for detecting the bending angle of the movable plate 4, a strain gauge 23 or a strain detecting element 23 such as a piezoresistive element attached to the movable plate 4 is used. There is. Therefore,
The bending angle θx of the movable plate 4 can be detected based on the change in the output value (resistance value) of the strain detection element 23.

FIG. 7 is a perspective view showing an optical scanning device C according to still another embodiment of the present invention. In this optical scanning device C, the permanent magnet 8 and the coil 9 are not used to drive the movable plate 4, and the space between the drive electrode 24 provided on the movable plate 4 and the drive electrode 25 provided on the fixed plate 6 is not used. The movable plate 4 is bent and deformed by an electrostatic force acting on the movable plate 4. For example, one drive electrode 2
4 (or 25) is kept at a negative potential, and the drive circuit 10
When the other drive electrode 25 (or 24) is switched between a positive potential and a negative potential at regular intervals by
The movable plate 4 is bent and deformed in the front-back direction and vibrates due to the electrostatic force between them, and the light beam α reflected by the reflecting surface 7 is scanned in two directions.

8A and 8B are a perspective view and a side view showing an optical scanning device D according to still another embodiment of the present invention. In this embodiment, the rotation block 3 is substantially L
The lower end portion of the movable plate 4 is supported by a fixed plate 6 that is bent in a V shape via a solid actuator 26 such as a laminated piezoelectric element. Then, when an AC voltage is applied to the solid-state actuator 26 such as the laminated piezoelectric element, the lower end portion of the movable plate 4 linearly vibrates, and this linear vibration is converted into the bending deformation mode vibration by the bending deformation portion 21. Therefore, when the movable plate 4 is vibrated in the bending deformation mode while rotating the rotating block 3 by the rotation driving unit 1, the light beam α reflected by the reflecting surface 7 is scanned in two directions.

FIG. 9 is a perspective view showing an optical scanning device E according to still another embodiment of the present invention. The optical scanning device E does not include the reflecting surface 7, and the light emitting element 1 such as a semiconductor laser element or a light emitting diode (LED) is provided on the tip side of the movable plate 4.
2 is attached. Then, this optical scanning device E
In this case, when the movable plate 4 is rotated in the θz direction and the θx direction, the light beam α emitted from the light emitting element 12 is two-dimensionally scanned.

FIG. 10 is a block diagram showing a control unit 28 for controlling the scanning angle of the reflection surface of the optical scanning device, for example, the optical scanning device A. The rotation angles θz and θx of the reflection surface 7 are target values θzo, It is controlled so as to match θxo. The target values θzo and θxo of the rotation angles θz and θx are set by the setting means 29. The actual rotation angle θz of the reflection surface 7 is detected by the rotation drive angle detection means 13, and the control unit 28 compares the set target value θzo with the detected rotation angle θz by the comparison means 30 to determine the reflection surface 7 Rotation angle θz and target value θ
An operation signal proportional to the difference (θzo-θz) is output to the circuit means 31 so that the difference of zo becomes small, and the circuit means 31 is arranged so that the rotation angle θz output from the rotation drive unit 1 becomes equal to the target value θzo. The rotation drive unit 1 is controlled by. Similarly, the actual rotation angle θx of the reflecting surface 7 is detected by the bending angle detection means 14, and the control unit 28 sets the set target value θxo.
And the rotation angle θx detected by the comparison means 32, and an operation signal proportional to the difference (θxo−θx) is sent to the circuit means 33 so that the difference between the rotation angle θx of the reflecting surface 7 and the target value θxo becomes small. The circuit means 33 outputs so that the rotation angle θx controlled by the bending deformation means becomes equal to the target value θxo.
Controls the current flowing through the coil 9.

As a result, the light beam α can be scanned at the scanning angles 2θz and 2θx corresponding to the set target value, and the light beam α can always be scanned at the position that coincides with the target. Further, since the control unit 28 forms a feedback loop, the angles θz and θ of the reflecting surface 7 are affected by a disturbance such as an impact.
Even if x is deviated, it is immediately corrected, the rigidity or stability of the entire control system is improved, and it becomes strong against external disturbance such as impact. Further, when used as a sensor for detecting the position of an object, accurate position information of the detected object can be obtained.

Although not shown, the setting means 29 sets the target value (θzo) max or (θxo) max of the rotation range of the light beam α.
By inputting, a feedback loop may be formed so that the actual rotation ranges (θz) max and (θx) max detected by the rotation drive angle detection means 13 and the bending angle detection means 14 become equal to their respective target values. . According to such a control unit 28, the light beam is accurately scanned in the scanning range (2θzo).
It is possible to scan at max, (2θxo) max.

FIG. 11 is a block diagram showing an embodiment of a laser distance measuring device G using the optical scanning device F of the present invention. The laser distance measuring device G includes an optical scanning device F of the present invention, a light source 12 including a light emitting element 41 such as a near infrared pulse laser and an optical element 42 such as a lens, a light receiving element 43 such as a photodiode, and a light emitting element 41. A drive circuit 44 for driving and emitting the optical pulse α1, a drive circuit 10 for driving the optical scanning device F, a signal processing circuit 46 for electrically processing a light reception signal from the light receiving element 43, and the drive circuits 44, 10 and signals. The control unit 47 controls the processing circuit 46.

In the laser distance measuring device G, the optical pulse α1 emitted from the light emitting element 42 is two-dimensionally scanned by the optical scanning device F toward the detection object 45. The light pulse α1 emitted at this time hits the detection object 45, and the detection object 4
The light receiving element 43 detects the light pulse α2 reflected from the light receiving element 5. Then, the light receiving signal output from the light receiving element 43 is amplified by the signal processing circuit 46, and the emitted optical pulse α1
By calculating the time delay of the received light pulse α2, the distance to the sensing object 45 can be measured.

FIG. 12 is a block diagram showing an embodiment of an optical sensor device H using the optical scanning device F of the present invention. This optical sensor device H includes an optical scanning device F of the present invention, a light emitting element 41 such as a semiconductor laser element, and an optical element 4 such as a lens.
Light source 12 consisting of 2 and light receiving element 4 such as a photodiode
3, a drive circuit 44 that drives the light emitting element 41 to emit the light beam α, a drive circuit 10 that drives the optical scanning device F, a signal processing circuit 46 that electrically processes a light reception signal from the light receiving element 43, and a drive Circuits 44 and 10 and signal processing circuit 4
It is composed of a control unit 47 for controlling the control unit 6.

The optical sensor device H emits the light beam α emitted from the light emitting element 41 toward the detection area by the optical scanning device F, and also emits the light beam α along the two-dimensional scanning pattern in the detection area. Scan α. At this time, if the detection object 45 exists in the detection area, the light beam α reflected by the detection object 45 is detected by the light receiving element 43. Then, the signal processing circuit 46 performs signal processing and signal analysis on the light reception signal output from the light receiving element 43 that has received the light beam α to determine whether or not the object 45 exists in the detection area, and further determines the shape of the object 45. Is detected.

FIG. 13 shows an embodiment of a code information reading device J using the optical scanning device F of the present invention. By using an optical sensor device having the same configuration as the optical sensor device H of FIG. 12 for the purpose of reading code information 48 such as a bar code, a multi-stage bar code, and a matrixed two-dimensional bar code,
A code information reading device J using the optical scanning device F of the present invention can be provided. However, since the light receiving element 43 receives the reflected light corresponding to the bar and the space of the barcode, the signal processing circuit 46 has a decoding function for decoding the barcode or the like from the received light signal.

[Brief description of drawings]

FIG. 1 is a perspective view showing an optical scanning device according to an embodiment of the present invention.

FIG. 2 is a side view of the above optical scanning device.

3A and 3B are partially cutaway side views for explaining the operation of the above optical scanning device.

FIG. 4A is a front view showing a movable plate having a different shape;
(B) is a side view showing a state of the bending deformation.

5A is a front view showing a movable plate having a different shape, and FIG. 5B is a side view showing a state of bending deformation thereof.

FIG. 6 is a perspective view showing an optical scanning device according to another embodiment of the present invention.

FIG. 7 is a side view showing an optical scanning device according to another embodiment of the present invention.

8A and 8B are a perspective view and a side view showing an optical scanning device according to still another embodiment of the present invention.

FIG. 9 is a perspective view showing an optical scanning device according to another embodiment of the present invention.

FIG. 10 is a block diagram showing a configuration of a control unit of the optical scanning device.

FIG. 11 is a block diagram showing a configuration of a laser distance measuring apparatus according to the present invention.

FIG. 12 is a block diagram showing a configuration of an optical sensor device according to the present invention.

FIG. 13 is a block diagram showing a configuration of a code information reading device according to the present invention.

FIG. 14 is a schematic perspective view showing a conventional optical scanning device.

FIG. 15 is a perspective view showing another conventional optical scanning device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotary drive part (rotary drive means) 2 rotary shaft 4 movable plate 6 fixed plate 7 reflective surface 8 permanent magnet 9 coil 10 drive circuit (control means) 12 light source 13 rotary drive angle detection means 14 bending angle detection means 15, 16 Electrode 19 Stopper 21 Bending deformation part (constriction part) 23 Strain detection element 24, 25 Drive electrode 26 Solid actuator 28 Control part 29 Setting means

Claims (16)

[Claims] 1. A reflection surface for reflecting light, a rotation driving means for rotating the reflection surface, and an angle formed by the reflection surface and a rotation axis of the rotation driving means, an electromagnetic force such as an electrostatic force or a magnetic force. An optical scanning device comprising: 2. The rotation driving means rotates the angle changing means together with the reflecting surface.
The optical scanning device according to. 3. The angle changing means includes a movable plate that can be bent and deformed, and the reflecting surface and the rotation axis of the rotation drive means are formed by bending the movable plate generated by an electromagnetic force such as an electrostatic force or a magnetic force. The angle is changed, and the angle is changed.
Or the optical scanning device according to item 2. 4. The angle changing means arranges a fixed plate and a movable plate so as to face each other, and each of the fixed plate and the movable plate is provided with a member that interacts with each other by an electromagnetic force such as an electrostatic force or a magnetic force. The optical scanning device according to claim 3, wherein the movable plate is provided with a reflecting surface. 5. The optical scanning device according to claim 4, wherein the fixed plate and the movable plate are partially fixed to each other, and the rotation driving means rotates the fixed plate and the movable plate together. 6. The optical scanning device according to claim 4, wherein a control means for controlling an electromagnetic force such as an electrostatic force or a magnetic force is provided on the back side of the fixed plate. 7. The optical scanning device according to claim 4, further comprising bending angle detection means for detecting an angle formed by the reflection surface and a rotation axis of the rotation drive means. 8. The bending angle detection means detects an angle formed by the reflection surface and a rotation axis of the rotation drive means based on an electrostatic capacitance between a fixed plate and a movable plate. The optical scanning device according to claim 7. 9. The bending angle detection means detects an angle formed by the reflection surface and a rotation axis of the rotation drive means based on a value of a strain detection element such as a strain gauge attached to a movable plate. The optical scanning device according to claim 7, wherein 10. The angle of the reflecting surface detected by the bending angle detecting means and a target value of the angle are compared so that the angle of the reflecting surface detected by the bending angle detecting means always matches the target value. The optical scanning device according to claim 7, wherein electromagnetic force such as electrostatic force or magnetic force is controlled. 11. The movable plate is formed with a constricted portion for causing bending deformation.
The optical scanning device according to claim 4. 12. The optical scanning device according to claim 4, wherein the movable plate is formed of a metal material having a large fatigue limit such as beryllium copper or phosphor bronze. 13. The optical scanning device according to claim 4, wherein the fixed plate is provided with a stopper for limiting a movable range of the movable plate. 14. A fixed plate, a movable plate which is bendable and deformable and is disposed so as to face each other with respect to the fixed plate, and the fixed plate and the movable plate are provided with electromagnetic force such as electrostatic force or magnetic force provided to each of them. Members that interact with each other, control means for controlling this electromagnetic force, a light source provided on the movable plate, and rotation driving means for rotating the fixed plate and the movable plate together in a direction different from the bending direction of the movable plate, An optical scanning device comprising: 15. The method for scanning light on a target object according to claim 1.
14. A distance measuring device, comprising: the optical scanning device according to claim 14; and a light receiving unit that receives reflected light from a target object, and measures the distance to the target object based on the received light signal. 16. The optical scanning device according to claim 1 for scanning a detection target with light, a light receiving element for detecting the intensity of reflected light from the detection target, and an electric signal output from the light receiving element. An optical sensor device that includes a signal processing unit that processes the information and that senses information such as a position, a shape, and a size of a detection target, or a mark, a pattern, a code, a character that is the detection target.