JP3467603B2 - Vibrating mirror scanning device - 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 information reading device for reading an optical information pattern recorded on an optical recording medium, and more particularly to a light beam scanning type optical information reading device and use thereof. Vibrating mirror type scanning device.

[0002]

2. Description of the Related Art As a light beam scanning device used in a conventional optical information reading device, a device using a polygon mirror and a rotary drive motor, or a device using a single-sided mirror and a galvano motor is generally used. is there. FIG. 7A
FIG. 6 is a perspective view of a light beam scanning device using a polygon mirror and a rotation drive motor. In the same figure (a), p
m is a polygon mirror and b m is a rotary drive motor. The polygon mirror pm and the rotary drive motor b m are separately formed as shown in the drawing, and are directly or connected to each other via a reduction mechanism. FIG. 7B is a perspective view of a light beam scanning device using a single-sided mirror and a galvano motor. In the figure (b), m is a single-sided mirror,
gm is a galvano motor. The single-sided mirror m and the galvano motor gm are configured separately from each other, as shown in the drawing, and the rotating shafts of both are directly coupled.

[0003]

2. Description of the Related Art In the above-mentioned light beam scanning device using a polygon mirror and a rotation driving motor, the polygon mirror pm and the rotation driving motor bm are separately constructed, and therefore, the height dimension (that is, rotation) is increased. It is difficult to further reduce the dimension in the axial direction, and since the rotation drive motor b m is used, the dimension in the front-rear direction (that is, the dimension in the direction perpendicular to the rotation axis direction) is further reduced. Difficult to do. Further, in the light beam scanning device using the single-sided mirror and the galvano motor, since the single-sided mirror m and the galvano motor gm are configured separately from each other, the height dimension (that is, the dimension in the rotation axis direction). ) Is further difficult to reduce, and since the galvanomotor gm is used,
It is difficult to further reduce the dimension in the front-back direction (that is, the dimension in the direction perpendicular to the rotation axis direction).

[0004]

SUMMARY OF THE INVENTION Therefore, a first object of the invention of this application is to further reduce the size in the height direction and the size in the front-back direction of a light beam scanning device. A second object of the invention of this application is to eliminate the need for a mechanical spring member in the oscillating mirror type scanning device, thereby extending the service life. A third object of the invention of this application is to further improve controllability in a vibrating mirror type scanning device. A fourth object of the invention of this application is to achieve the above objects with a simple structure and at low cost.

[0005]

[Means for Achieving the Purpose] Solving the above problems,
In addition, in order to achieve the above-mentioned various objects, according to the invention of this application,
The oscillating mirror scanner consists of at least one reflection mirror.
-And, The movable part 2, HoRuda 6, fixed yoke 7, drive winding
Using the wire 9, the movable part 2 includes a movable part main body and a rotary shaft 25.
And the movable part main body has a plate shape, a rod shape, or a three-dimensional shape.
Form a pair of opposite sides 7 of fixed yoke 7₁, 7_TwoIn betweenSetting
Shi, PermanentEither install the permanent magnet inside the movable part main body, orIs permanent
It is common to dispose a permanent magnet between the movable part body and the fixed yoke 7.
Whether the magnetic body is placed inside the movable part body
A magnetic circuit that passes through the main body and the fixed yoke 7 is configured and driven.
The winding 9 is formed by the above magnetic circuit.WhatBetween the moving part body and the fixed part
That can cross the spatial magnetic field generated in the air gap of
The rotation shaft 25 can be freely rotated by the holder 6.
SupportConsentShi, Anti-the aboveShooting miraIs, Fixed to the front of the movable part body
Do, ThingIt

[0006]

A movable body SUMMARY OF THE INVENTION are respectively disposed between the opposite sides _71, 7 ₂ and the movable portion 2 of the opposite sides 7 _1, 7 2 _(or fixed yoke 7 fixed yoke 7 of the outer The attraction force always acts between the permanent magnets). In other words, the magnetic spring force acts on the movable part body to restore it to the rest position (the position where the front surface of the movable part body is parallel to the plane including the fixed yoke 7). Is there. Therefore, when current is not supplied to the drive winding 9, the movable portion 2 is freely displaced after being slightly displaced from the rest position and then alternately rotated in the forward direction or the reverse direction. While restoring to the rest position. The frequency of free vibration (resonance frequency) is determined by the magnetic spring force and the moment of inertia of the movable part.

[0007] supplying an alternating current to the driving coil 9, Koban field across the movable unit 2 is generated. As a result, a forward or reverse rotational force is alternately generated in the movable portion 2. The movable portion 2, and the magnetic spring force by the permanent magnet, acts alternating rotational force is at the same time by the alternating electromagnetic field, when rotation angle is small, the magnetic spring towards the alternating rotational force by Koban magnetic field by the permanent magnet Conversely, when the rotation angle is larger than the force and the rotation angle is large, the magnetic spring force of the permanent magnet becomes larger, so that the movable portion 2 performs the reverse rotation vibration. The vibration frequency of the reversing rotational vibration (forced vibration) in the steady state is determined by the frequency of the alternating current, and the amplitude is determined by the magnetic spring force, the rotational force by the alternating electromagnetic force, and the moment of inertia of the movable part. . The waveform of the reverse rotational vibration (forced vibration) in the transient state is given by solving the second-order differential equation.

The vibrating mirror type scanning device according to the invention of this application is used in a resonant mode or a non-resonant mode. When the movable unit 2 is a rotated in the reverse direction vibration, the first reflecting mirror light beam incident on (scanning mirror) 1 ₁ of the front surface of the movable section 2 is scanned on the optical information pattern on P, also the optical information from the pattern P, the second reflecting mirror reflected light arriving at (receiving mirror) 1 ₂ of the rear surface of the movable portion 2 is guided to the light receiving surface of the photoelectric conversion unit PD.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the vibrating mirror type scanning device of the invention of this application will be described. FIG. 1 shows the same as the first embodiment.
A diagram, (a) is a horizontal sectional view, (b) is a vertical sectional view. In FIG. 1, ₁₁ is a first reflection mirror,
1 ₂ is a second reflecting mirror, 2 is a movable part, 6 is a holder, 7
Is a fixed yoke and 9 is a drive winding.

First, the above-mentioned elements and the relationship between the above-mentioned elements will be described. The movable part 2 includes a movable part body and a rotary shaft 2.
5 and. The movable part body has a plate shape, a rod shape, or a three-dimensional shape, and includes two movable magnets 21 and 21 and a movable yoke 22.
Contains and. The movable yoke 22 includes two movable magnets 21,
Between the two, they are magnetically and mechanically coupled.
However, in this specification, "yoke" means a magnetic circuit portion made of a magnetic material. The rotary shaft 25 coincides with the vertical principal axis of inertia of the movable portion 2. The mass distribution on the left and right of the rotary shaft 25 is symmetrical and balanced. Movable magnet 21,
Are magnetized in a direction orthogonal to the rotation axis 25.
The fixed yoke 7 includes a pair of opposite sides 7 ₁ and 7 ₂ running vertically and
Containing another pair of opposite sides connecting these (unsigned), its shape is typically approximately closed-shape. Across flats ₇ 1, _{7 2} of the pair of fixed yoke 7, FIG. 1, (see Fig. (A)) even in horizontal cross section, in vertical section (Fig. (B)
Although it is linear, it is possible to form a gentle arc or curve on any surface. The shape of the drive winding 9 of this embodiment is substantially square-shaped and is similar to the shape of the fixed yoke 7.

The holder 6 has a pair of upper and lower bearings.
Pivot shaft 25 is Seung supported rotatably by a pair of bearings in the holder 6. The movable portion 2 is placed between the opposite sides _{71, 7 2} of the pair of fixed yoke 7. The shape of the left and right end portions of the movable portion 2, in the same manner as the opposite sides _71, 7 ₂ of the shape of the fixing yoke 7 can be a gentle arc shape or curve shape. The movable part main body and the fixed yoke 7 constitute a magnetic circuit in a substantially letter V shape. The drive winding 9 is arranged concentrically with the fixed yoke 7. The first reflection mirror (scanning mirror) ₁ is a movable part 2
Fixed to the front surface of the second reflection mirror (light receiving mirror)
1 ₂ is fixed to the rear surface of the movable portion 2. The number of movable magnets of the movable portion main body may be one or three or more. A non-magnetic material may be used instead of the movable yoke 22. The holder 6, the fixed yoke 7 and the drive winding 9 form a fixed portion. The vibrating mirror type scanning device of the invention of this application can be designed to be large or small. When designing a small size, for example, length 1 cm, width 2 cm, thickness (depth) 1.5 cm
Can be set to In addition, vertical, horizontal, thickness
It can be one-fourth or less.

Next, the overall operation of the first embodiment will be described. Between the movable magnets 21 and 21 of the movable portion main body and the opposite sides 7 ₁ and 7 _{2 of} the fixed yoke 7 which are adjacent to them, always,
The attractive force of the static magnetic field is acting. In other words, with respect to the movable part 2, it is attempted to restore it to a stationary position (the position shown in the drawing; the position where the movable magnet 21 and the opposite sides 7 ₁ , 7 _{2 of the} fixed yoke 7 are closest to each other). Magnetic spring force (rotational moment) is acting. The magnitude of the magnetic spring force is approximately as follows. Magnetic spring force (rotational moment) = k · sin θ (1) where k is the spring constant (a constant proportional to the attractive force of the movable magnet), θ is the rotation angle of the movable part main body (rotation with respect to the plane including the yoke 7). Dynamic angle). Therefore, if current is not supplied to the drive winding 9, the movable portion main body is alternately displaced from the rest position and then released, and then the movable portion main body alternately turns in the forward direction or the reverse direction to change the amplitude. Restores to the rest position while attenuating. The vibration equation at this time is approximately as follows. I (dθ ² / dt ² ) + c (dθ / dt) + k · sin θ ± f = 0 (2) where I is the moment of inertia of the movable part 2, θ is the rotation angle of the movable part 2, and c is the viscous damping constant. , K is a spring constant (a moment required to twist a unit angle and is a constant proportional to the suction force), f is a dry friction force, and t is a time. When the dry frictional force f can be ignored, it is approximately as follows. I (dθ ² / dt ² ) + c (dθ / dt) + k · sin θ = 0 (3) As is easily understood from the formula (2), the natural angular frequency (resonance frequency) of the movable part 2 is moment of inertia I, the spring constants k, therefore is determined by the suction force of the movable magnet 21. When the shapes of the opposite sides 7 ₁ and 7 ₂ of the fixed yoke 7 and the left and right end portions of the movable magnets 21 and 21 are arcuate in a horizontal cross section, the gap of the void is increased as the rotation angle θ increases. Since the degree of increase in magnetic energy is reduced, the attractive force between the opposite sides 7 ₁ and 7 ₂ and the movable magnets 21 and 21 is reduced. Therefore, there is an advantage that the spring constant is reduced and the natural angular frequency (resonance frequency) of the movable portion 2 is reduced.

[0013] supplying an alternating current to the driving coil 9, Koban field across the moving magnet 21 of the movable body in the same direction is generated. This Koban field, the movable body,
Rotational moments in the forward and reverse directions alternate. Magnitude of the rotational moment due Koban magnetic field, is approximately as follows. Rotation moment by Koban field = (T · cosωt) cosθ ( 4) where, T is a constant proportional to the AC current, omega is the angular <br/> frequency of the alternating current. The movable body, a magnetic spring force by the permanent magnet and the (k · sinθ), rotational moment (T · cosωt) by Koban field and cosθ acts simultaneously parallel manner. The vibration equation at this time is approximately as follows. I (d ² θ / dt ² ) + c (dθ / dt) + k · sin θ = · cos ωt) cos θ (5) where I is the moment of inertia of the movable part 2, θ is the rotation angle of the movable part 2, and c is the damping. Coefficient, k is a constant proportional to suction force, t
Is time, T is a constant proportional to the amplitude of the alternating current, and ω is the angular frequency of the alternating current. As can be easily understood from the equation (4), the angular frequency and the amplitude of the reversing rotational vibration (forced vibration) in the steady state are determined by the amplitude of the alternating current and the frequency ω.
When the rotation angle θ of the movable portion 2 is small, sin θ≈θ, c
Since os θ ≈1, the vibration equation (4) can be approximated by the following equation. I (d ² θ / dt ² ) + c (dθ / dt) + kθ = T · cosωt (6) The approximate waveform of the reversal rotational vibration (forced vibration) in the transient state solves the above vibration equation (6). By
You can get to know it. When the movable unit 2 is a rotated in the reverse direction vibration, the light beam, the optical information pattern P incident on the first reflecting mirror (scanning mirror) 1 ₁ of the front surface of the movable portion 2
The movable portion 2 is scanned from above and the optical information pattern P
Second reflecting mirror reflected light arriving at (receiving mirror) 1 ₂ of the rear surface of, is received by the light receiving surface of the photoelectric conversion element PD.

The vibrating mirror type scanning device according to the invention of this application is used in a resonant mode or a non-resonant mode. In the resonance mode, the frequency of the alternating current supplied to the drive winding 9 and the natural angular frequency (resonance frequency) of the movable portion 2 are
Make them the same. The resonance frequency of the movable part 2 is adjusted by adjusting the inertia moment I of the movable part 2 and / or the magnetic spring force of the movable magnets 21 and 21. The characteristics of the resonance mode are as follows. Operating in it resonance frequency <br/> only. Operates with sinusoidal vibration. The operating current can be extremely reduced . Practical application of 5 mA or less is possible.
The amplitude (scan width) can be controlled by the supply current. There is a possibility of 100 scan / sec or more.

In the non-resonant mode, the frequency ω of the alternating current supplied to the drive winding 9 must be considerably smaller (or larger) than the resonant frequency of the movable section 2. In this way, the disturbance of the waveform (shift from the sine wave) at the time of transition can be avoided. The characteristics of the non-resonant mode are as follows. It is necessary to operate in a frequency region sufficiently lower than the resonance frequency. It is possible to follow the supply current waveform. The scanning speed, scanning width, linear velocity, etc. can be controlled arbitrarily. In the non-resonant mode, internal loss or external damper can be added. Furthermore, as the over-dump, aperiodic motion (creep-like motion) can be performed. In this case, the controllability is further improved.

A second embodiment of the vibrating mirror type scanning device of the invention of this application will be described. Figure 2 is an explanatory view of the second embodiment, (a) is a horizontal sectional view, (b) is a vertical sectional view. 2, 1 ₁ a first reflecting mirror, 1 ₂ and the second reflecting mirror, 2 is movable unit, 6 holder 7 fixed yoke, 9 is a driving winding. Differences in configuration between the first embodiment and the second embodiment will be described. The fixed yoke 7 has a substantially U-shape or an inverted U-shape (in other words, a substantially U-shape rotated by 90 degrees clockwise or counterclockwise). And a pair of opposite sides 7 ₁ and 7 ₂ and another side (unsigned) connecting both sides. Movable body is placed between the opposite sides _71, 7 ₂ of the pair of fixed yoke 7. The movable part main body and the fixed yoke 7 constitute a magnetic circuit having a substantially square V shape. The rest of the configuration of the second embodiment is the same as that of the first embodiment.

In comparison with the first embodiment, of the second embodiment,
The difference in operation will be described. The fixed yoke 7 of the second embodiment is equivalent to one obtained by removing one side of the square-shaped fixed yoke of the first embodiment, so that the magnetic resistance of the magnetic circuit increases and the opposite sides 7 ₁ , 7 are formed. The magnetic flux density of the air gap between ₂ and the movable magnets 21 and 21 decreases. Therefore, the magnetic spring force is reduced and the resonance frequency is reduced. The degree of freedom in design increases accordingly. However, at the opening (upper part) of the fixed yoke 7,
The alternating magnetic field is a little disliked to spread outwards. Second
The remaining operation of this embodiment is the same as that of the first embodiment.

A third embodiment of the vibrating mirror type scanning device of the invention of this application will be described. Figure 3 is an explanatory view of the third embodiment, (a) is a horizontal sectional view, (b) is a vertical sectional view. 3, _{1 1} a first reflecting mirror, _{1 2} and the second reflecting mirror, 2 is movable unit, 6 the holder, the fixed yoke 7, the stationary magnet 8,8, 9 in the drive winding is there. Differences in the configuration of the third embodiment from the first embodiment will be described. The movable portion 2 includes a movable portion main body and a rotating shaft 25. The movable part body has a plate shape, a rod shape, or a three-dimensional shape, and contains one magnetic body 24. Movable body is placed is <br/> be between opposite sides _71, 7 ₂ of the pair of fixed yoke 7. The fixed magnets 8 and 8 are arranged between the movable portion main body and the pair of opposite sides 7 ₁ and 7 ₂ of the fixed yoke 7. The movable part main body, the fixed magnets 8 and 8 and the fixed yoke 7 constitute a magnetic circuit in the shape of a letter. The magnetic material is divided into two or more,
A non-magnetic material can be inserted between them. The rest of the configuration of the third embodiment is the same as that of the first embodiment.

In contrast to the first embodiment, of the third embodiment,
The difference in operation will be described. Magnetic body 24 of movable part main body
Between the fixed magnets 8 and 8 which are close to the
The attractive force of the static magnetic field is acting. In other words, a magnetic spring force (rotational moment) acts on the movable portion 2 to restore it to the rest position (position shown in the figure). Also for the third embodiment, the above equations (1) to
(6) is established. However, the spring constant k in the above equations (1) to (6) is a constant proportional to the attractive force of the fixed magnets 8, 8. The resonance frequency of the movable part 2 is adjusted by adjusting the moment of inertia I of the movable part 2 and / or the magnetic spring force of the fixed magnets 8, 8. In this embodiment, all or part of the magnetic body 24 can be replaced with a permanent magnet. In this case, the thickness (length in the magnetic circuit direction) of the fixed magnets 8, 8 can be reduced. Third
The remaining operation of this embodiment is the same as that of the first embodiment.

A fourth embodiment of the vibrating mirror type scanning device of the invention of this application will be described. 4A and 4B are explanatory views of the fourth embodiment, wherein FIG. 4A is a horizontal sectional view , FIG. 4B is a front view , and FIG. 4C is a side view. In FIG. 4, ₁₁ is a reflection mirror, 2 is a movable part, 6 is a holder, 7 is a fixed yoke, and 9 is a drive winding. The difference in configuration between the first embodiment and the fourth embodiment will be described. The fixed yoke 7 has a substantially U-shape. The substantially U-shape is a shape in which one side of the substantially U-shape is deleted. Across flats 7 _1, 7 ₂ of the pair of fixed yoke 7, which is typically a linear, it can be a gentle curved shape.

The movable part 2 includes a movable part main body and a rotary shaft 25. Movable body, while the opposite sides 7 _1, 7 ₂ of the pair of fixed yoke 7, placement of <br/> are in且前surface closer (open end closer). The movable part main body and the fixed yoke 7 constitute a magnetic circuit having a substantially square V shape. Pivot shaft 25, to the plane including the fixed yoke 7 is placed vertically. The drive windings 9 and 9 are wound around the pair of opposite sides 7 ₁ and 7 ₂ of the fixed yoke 7 toward the front. The only reflection mirror (scanning mirror) 1 ₁ is
It is fixed to the front surface of the movable portion 2. The remaining structure of the fourth embodiment is the same as that of the first embodiment.

In comparison with the first embodiment, the fourth embodiment
The difference in operation will be described. Movable magnet 2 of movable body
1, 21 and the opposite side 7 ₁ , 7 of the fixed yoke 7 adjacent thereto
_An attractive force due to a static magnetic field always acts between the _two . In other words, with respect to the movable part 2, the movable part 2 is placed at a stationary position (the position shown in the drawing. The movable magnet 21 and the opposite side 7 ₁ , of the fixed yoke 7).
7 ₂ and is trying to restore the position) closest together, the magnetic spring force (torque) is exerted.

When an alternating current is supplied to the drive windings 9, 9,
Koban <br/> magnetic field across the moving magnet 2 1, 2 1 of the movable body in the same direction is generated. This Koban field, the movable body, a rotational moment in the forward or reverse direction, alternately generated. Also for the first embodiment, the above equations (1) to
(6) is established. When the movable part 2 undergoes reverse rotation vibration,
The light beam incident on the reflecting mirror (scanning mirror) 1 ₁ of the front surface of the movable section 2 is scanned on the optical information pattern on P. The remaining operation of the fourth embodiment is the same as that of the first embodiment. In addition, FIG. 5 is a modification of the fixed yoke 7 of the fourth embodiment.
It is a figure which shows a modification, (a) is a top view, (b) is a front view.
It is a figure. In FIG. 5, 1 is a reflection mirror and 2 is movable
, 21 and 21 are the movable magnets, 7 is a fixed yoke, and R is
Is an arc-shaped portion of. The operation of this modified example is described in paragraph 1 above.
The operation is the same as the operation described in the latter part of 2.

A fifth embodiment of the vibrating mirror type scanning device of the invention of this application will be described. The fifth embodiment is the third
In this embodiment, the fixed yoke 7 is omitted altogether. For the fixed magnets 8 and 8, a magnetic material that is stronger than that is used. The other matters of the fifth embodiment are the same as those of the third embodiment.

The sixth, seventh and eighth embodiments of the vibrating mirror type scanning device of the invention of this application will be described. In the sixth, seventh , and eighth embodiments, the fixed yoke 7 in the first, second, and fourth embodiments is all omitted. However, the rest position must be determined by the current magnetic field.
In these examples, the degree of freedom in electrical control is increased.
The other matters of the sixth, seventh and eighth embodiments are the same as those of the first, second and fourth embodiments.

The ninth, tenth, eleventh, twelfth, thirteenth, fourteenth and first of the vibrating mirror type scanning device of the invention of this application.
The fifth and sixteenth embodiments will be described. 9th, 10th,
The eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth examples are the first, second, third, fourth, fifth, sixth, seventh,
A mechanical spring is added to the eighth embodiment. Mechanical springs include coil springs, spiral springs,
An air spring or the like is used. In these embodiments, the degree of freedom in designing the spring constant and thus the resonance frequency is increased.

An optical information reader according to the invention of this application will be described. FIG. 6 is a schematic view of the optical information reading device of the invention of this application. In FIG. 6, LF is a light beam forming unit, VM is an oscillating mirror type scanning device, CP is a condenser lens / reflection prism, PD is a photoelectric conversion unit, SP is a signal processing unit, and AD is an AC current supply device. The vibrating mirror type scanning device VM includes the first to third and fifth to first
This is the same as the first and thirteenth to sixteenth embodiments. In the light beam forming means LF and the vibrating mirror type scanning device VM, the light beam from the light beam forming means LF is reflected by the _first reflection mirror 11 to irradiate the optical information pattern P on the member to be read. as to, as illustrated, it is placed. The condenser lens / reflection prism CP and the vibrating mirror type scanning device VM perform photoelectric conversion of the reflected light from the optical information pattern P via the _second reflecting mirror 12 of the vibrating mirror type scanning device VM. as is guided to the light receiving surface of the unit PD, as shown, are placed. In this specification, the "reflection prism" is a prism that can reflect a ray bundle and change its direction, and is a general term for a right-angle prism, an erecting prism, a pentagonal prism, and the like. The combination of the elements CP and VM is hereinafter referred to as "scanning light receiving optical system". All or some of the above-mentioned various elements are housed in an appropriate housing (not shown). The condenser lens / reflection prism CP can be divided into a condenser lens and a reflection prism. The reflecting prism can be further generalized to a light redirecting means.

[0028] Scanning light receiving optical system, compared to the fixed-type light-receiving optical system, the light receiving efficiency, the pair disturbance light characteristic is advantageous. Further, the size of the optical filter to be added can be reduced.
Further, since the rear surface of the vibrating mirror type scanning device VM can be separated and used only for receiving light, it can be less affected by internal reflection. Generally, in the scanning type light receiving optical system, the reflection mirror 1 is used.
_Since the _second area is a light-receiving aperture, but must operate a relatively large mirror, in this embodiment, the light-receiving aperture, than the area of the reflecting mirror 1 _2, equivalently, it is possible to increase.

Another embodiment will be described. Other examples are the above-mentioned examples and the following matters (a) to
It is generated by combining with (C). (A) The pair of drive windings 9 and 9 of the fourth embodiment are removed, and instead, one drive winding similar to that of the first embodiment is provided inside the fixed yoke 7. You can do it. (B) By changing the arrangement order of the fixed yoke 7 and the drive winding 9 arranged in the same plane, the fixed yoke 7 may be arranged inside and the drive winding 9 may be arranged outside. I can. (C) The waveform of the supply current can be a square wave, a triangular wave, or any other periodic waveform.

[0030]

Since the invention of this application is constituted as described above, the following remarkable effects can be obtained. (A) It is possible to further reduce the height dimension, the front-rear dimension, and the lateral dimension of the beam scanning device. (B) In the oscillating mirror type scanning device, a mechanical spring member is not required, and thus the service life can be extended. (C) The controllability of the vibrating mirror type scanning device can be further improved. (D) When used in the resonance mode, the operating current can be extremely reduced. For example, it can be 5 mA or less. (E) When used in the non-resonant mode, it is possible to follow an arbitrary supply current waveform. Therefore, the scanning speed, the scanning width, the linear speed, etc. can be arbitrarily controlled. (F) Moreover, the structure is simple and the cost is low.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view and a vertical sectional view of a vibrating mirror type scanning device according to a first embodiment of the present invention.

FIG. 2 is a horizontal sectional view and a vertical sectional view of a second embodiment of an oscillating mirror type scanning device according to the invention of this application.

FIG. 3 is a horizontal sectional view and a vertical sectional view of a vibrating mirror type scanning device according to a third embodiment of the present invention.

FIG. 4 is a horizontal sectional view, a front view, and a side view of a vibrating mirror type scanning device according to a fourth embodiment of the present invention.

FIG. 5 is a plan view and a front view showing a modified example of the fixed yoke of the fourth embodiment.

FIG. 6 is a schematic diagram of an optical information reading device according to the invention of this application.

FIG. 7 is a perspective view of a conventional scanning mirror device.

[Description of Reference Signs] 1 reflection mirror 1 ₁ first reflection mirror 1 ₂ second reflection mirror 2 movable part 21 movable magnet 22 movable yoke 24 magnetic body 25 rotating shaft 6 holder 7 fixed yoke 7 ₁ fixed yoke Opposite side 7 ₂ Opposite side of fixed yoke 8 Fixed magnet 9 Drive winding LF Light beam forming means VM Vibrating mirror type scanning device CP Condenser lens / reflection prism PD Photoelectric conversion means R Fixed yoke arc portion SP Signal processing unit b m rotation drive motor gm galvano motor pm polygon mirror m single-sided mirror

Claims (9)

(57) [Claims] 1. A first reflecting mirror (1 ₁ ), a movable part (2), a holder (6), a fixed yoke (7) and a drive winding (9) having a substantially square V shape. The movable part (2) includes a movable part body and a rotating shaft (25), and the movable part body has a plate shape, a rod shape, or a three-dimensional shape.
Or a plurality of movable magnets (21, ...) Is contained, the movable magnets (21, ...) Are magnetized in a direction orthogonal to the rotation axis (25), and the fixed yoke (7) is is configured to shape or inverted U-shaped-shaped or substantially U of approximately closed, the movable body, said stationary yoke (7) of a pair of opposite sides (7 _1), (7 ₂₎ placed between is, the above-mentioned movable body and the fixed yoke (7), a magnetic circuit of the shape of the shaped or approximately closed substantially date, shafts the times (25), the pair of opposite sides (7 ₁ ), (7
₂₎ and arranged in parallel, by the holder (6) is Approved supported rotatably, said drive winding (9) is concentrically arranged with the fixed yoke (7), the first reflector mirror (1 ₁₎ is fixed to the front surface of the movable portion (2), the oscillating mirror type scanner. 2. A second reflection mirror (1 ₂ ) is also included, said second reflection mirror (1 ₂ ) being fixed to the rear surface of said movable part (2). An oscillating mirror scanning device as described . 3. A first reflecting mirror (1 ₁ ), a movable part (2), a holder (6), a fixed yoke (7), and one or two fixed magnets (8, ...). , A drive winding (9) having a substantially square shape, the movable part (2) includes a movable part main body and a rotating shaft (25), and the movable part main body is plate-shaped, rod-shaped or three-dimensional. It ’s like 1
Or a plurality of magnetic bodies (24, ...), The fixed yoke (7) is formed in a substantially mouth shape, a substantially U shape, or an inverted U shape, yoke (7) opposite sides ₍₇ 1) of a pair of, _{(7 2)} is placed between said fixed magnet (8, ...), said fixed above opposite sides of the yoke (7) ₍₇ 1) , between the movable body _{(7 2),}
Moreover, the movable part main body, the fixed magnets (8, ...) And the fixed yoke (7), which are arranged on a line orthogonal to the rotating shaft (25), have a substantially day shape or a substantially a magnetic circuit of the mouth of the shaped shaft the times (25), the pair of opposite sides ₍₇ 1), (7
₂₎ and arranged in parallel, by the holder (6) is Approved supported rotatably, said drive winding (9) is concentrically arranged with the fixed yoke (7), the first reflector mirror (1 ₁₎ is fixed to the front surface of the movable portion (2), the oscillating mirror type scanner. 4. Furthermore, the second also contain a reflection mirror (1 _2), a reflecting mirror of the second (1 _2), the is fixed to the rear surface of the movable part (2), according to claim 3 An oscillating mirror scanning device as described. 5. A reflecting mirror (1 ₁ ) and a movable part (2)
When a holder (6), solid TeiTsugitetsu and (7), one or two drive windings (9, ...) contains a, the movable part (2) is movable body and the pivot shaft ( 25) and the movable part main body is plate-shaped, rod-shaped or three-dimensional
Or a plurality of movable magnets (21, ...) Is contained, the movable magnets (21, ...) Are magnetized in a direction orthogonal to the rotation axis (25), and the fixed yoke (7) is , substantially U-shaped, or constructed in front of the movable body in the shape of diverted deformed opening, the movable body, said pair of opposite sides of the stationary yoke (7) (7 _1), (7 ₂₎ It is placed between the plane the movable body and the fixed yoke (7), a magnetic circuit of the approximately closed-shape, shaft the times (25), comprising the fixed yoke (7)
Arranged perpendicularly to, by the holder (6) is Approved supported rotatably, said one or two drive winding (9), said opposite sides of said fixed yoke (7) (7 ₁₎ , (7 ₂₎ wound routed to, the reflecting mirror (1 ₁₎ is fixed to the front side of the movable portion (2), the oscillating mirror type scanner. 6. over the maximum angle rotational position from the neutral angle position of the movable magnet (21, ...), may be facing its outer end, each opposite side _(71), (7 ₂₎ the shape, the rotation plane, becomes configured in an arc shape, the oscillating mirror type scanner according to any one of claims 1 to 5. 7. A light beam forming means (LF);
Or 4 vibration mirror type scanner according with (VM), a condenser lens, and the light redirecting means, the photoelectric conversion means (PD),
The light beam forming means (LF) and the vibrating mirror type scanning device (VM) include a signal processing unit (SP) and a housing that houses all or some of these elements. The light beam from the forming means (LF) is arranged so as to be reflected by the first reflecting mirror (1 ₁ ) and scan the optical information pattern (P) on the member to be read, the light direction changing means. And the photoelectric conversion means (PD)
The reflected light from the optical information pattern (P) is guided to the light receiving surface of the photoelectric conversion means (PD) via the _second reflecting mirror (1 ₂ ) of the vibrating mirror type scanning device (VM). as light is disposed, the optical information reading apparatus. 8. The light redirecting means is a reflecting prism.
Rannahli, and the condenser lens and the upper Symbol reflecting prism, taken together are turned into a condenser lens and a reflecting prism (CP), an optical information reading apparatus according to claim 7 wherein. 9. The optical information reading device according to claim 7 , wherein the housing has a hand-held structure.