JP2002372681A - Galvanomirror - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a galvanomirror by which vibration in a direction perpendicular to a direction in which a supporting member to turnably support a mirror around two shafts is extended is reduced. SOLUTION: A spring to freely rotatably support a mirror holder 18 to which the mirror is attached around rotary shafts 8 and 9 consists of a first deformed part 23a and a second deformed part 23b provided at end parts and a connecting part 23c to connect them, and a thin plate is formed in parallel with a plane including the rotary shafts 8 and 9 by etching, and since rigidity in a Z-direction perpendicular to the plane specially at the connecting part is deteriorated as it is, an outer peripheral part 23c-2 whose rigidity in the Z-direction is enhanced by plastic-molding is provided at the connecting part 23c, so that unnecessary vibration is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recording and / or recording information on an optical recording medium such as a magneto-optical disk drive, a write-once disk drive, a phase-change disk drive, a CD-ROM, a DVD, and an optical card. Also, the present invention relates to a galvanomirror used for an information recording / reproducing apparatus for reproduction, an optical scanner, an optical deflector for optical communication, and the like.

[0002]

2. Description of the Related Art Magneto-optical disk drives, write-once disk drives, phase change disk drives, CD-ROs
2. Description of the Related Art In an optical device such as an information recording / reproducing device for recording and / or reproducing information on an optical recording medium such as an M, a DVD, an optical card, or the like, or an optical device such as an optical scanner, an optical device such as a mirror is used to tilt a light beam. A galgano mirror that rotatably supports the element is used.

A galvanometer mirror is disclosed in, for example,
000-275573 discloses an apparatus as shown in FIG. In the planar type two-axis galvanometer mirror, two permanent magnets 71 are arranged diagonally outside a semiconductor element 70 made of a silicon substrate. Semiconductor element 70
On the inner movable plate 72, a driving thin film coil 74 for driving the inner movable plate 72 is formed in a frame shape so as to surround the total reflection mirror 73.

The inner movable plate 72 and the outer movable plate 75 are formed integrally with a torsion bar 72A, 72B made of a silicon substrate.
Connected with. The outer movable plate 75 is connected to the frame portion of the silicon substrate by torsion bars 75A and 75B. On the upper surface of the outer movable plate 75, a driving thin-film coil 76 for driving the outer movable plate 75 is formed.

When a current is applied to the driving thin-film coil 76 formed on the outer movable plate 75, the first torsion bar 75A,
The outer movable plate 75 rotates in accordance with the current direction with the fulcrum 75B as a fulcrum. At this time, the inner movable plate 72 also rotates integrally with the outer movable plate 75. On the other hand, when an electric current is applied to the driving thin film coil 74 formed on the upper surface of the inner movable plate 72, the inner movable plate 72 rotates around the second torsion bars 72A and 72B as a fulcrum. An electric current flows through the driving thin-film coil 76 of the outer movable plate 75, and the driving thin-film coil 74 of the inner movable plate 72
When an electric current is applied to the outer movable plate 76, the outer movable plate 76 can be rotated, and the inner movable plate 72 rotates in a direction perpendicular to the rotation direction.

In this case, two-dimensional scanning can be performed by scanning the polarization of the laser beam with the total reflection mirror 73. The windows 78A, 78 are formed around the movable plates 75, 72 by etching.
B, 79A, 79B are formed, and the movable plates 75, 7
2 is a torsion bar 75A, 75B, 72A, 72B,
Only held by.

The torsion bars 72A, 72B, 75A, 75B for supporting the total reflection mirror 73 and the outer movable plate 7
Reference numeral 5 extends along a plane parallel to the reflection surface of the total reflection mirror 73. Note that the semiconductor element 70 is mounted on the pedestal 59. The semiconductor element 70 is provided with electrode patterns 97A, 97B, 98A, 98B.

In the case of a galvanomirror, it is important that the light reflected on the reflecting surface be stable. For this reason, as shown in FIG. 18, a hole is provided in the center of a bottom wall 82 of a base member 81 formed by press molding, and the lower surface of the bottom wall 82 is formed in a spherical shape as shown in FIG. And then
A mounting surface 83 is provided for mounting and adjusting the galvanometer mirror 80.

A spring assembly 84 is housed in the base member 81. This spring assembly 84 includes
It comprises a cantilever-shaped fixing member 85 and a movable member 86 rotatably supported on the front side of the fixing member 85. This movable member 86 is moved by springs 87 and 88 as shown in FIG.
It is supported rotatably about a mirror rotation axis R parallel to the axis.

A mirror 89 is attached to the front surface of the movable member 86, and a movable coil 90 is attached so as to surround the mirror 89. The movable member 86, the mirror 89, the movable coil 90 and the like are used. A movable part is formed. The base member 8 on the front side of the mirror 89
1 is notched and opened, and an opening 91 through which light passes is formed.

The movable coil 90 has lead wires 92 extending from upper and lower portions thereof. Further, magnets 93 are arranged and fixed in gaps on both sides of the spring assembly 84. A flat portion 94 is formed in a portion where the magnet 93 is stored. The springs 87 and 88 have an S-shaped spring portion 95 formed in an S shape, a reinforcing conductive portion (not shown) formed continuously from the S-shaped spring portion 95, and a terminal portion.

In this manner, the mirror 8 is attached to the movable member 86.
9 and the movable coil 90, and two S-shaped springs 8
7 and 88, the both ends of the movable member 86 are connected to the fixed member 85, two magnets 93 are arranged on the base member 81 side so as to face two sides of the movable coil 90, and
The mirror 89 is rotatably supported around an axis so that a current can flow through the movable coil 90 to drive the mirror 89 to rotate.

There is disclosed a galvano mirror 80 in which such springs 87 and 88 are extended in a direction perpendicular to the reflecting surface of the mirror 89 to increase rigidity in a direction perpendicular to the reflecting surface of the mirror 89. However, since the galvanometer mirror 80 is driven by one axis having one rotation axis, it is easy to configure a support member having high rigidity in a direction perpendicular to the reflection surface.

In Japanese Patent Laid-Open No. 2000-275573, which discloses a galvano mirror for tilting a mirror about two axes, a torsion bar 72 for supporting a total reflection mirror 73 is disclosed.
A, 72B, 75A, 75B and the outer movable plate 75 extend along a plane parallel to the reflection surface of the total reflection mirror 73.

[0015]

Therefore, the rigidity in the direction perpendicular to the reflection surface, that is, in the direction perpendicular to the plane in which the support member extends, is low, and the support member extends due to external vibration and resonance of the support member. It has the drawback that it is easy to move in the direction perpendicular to the existing plane, and that the light reflected by the total reflection mirror also vibrates unnecessarily.

(Object of the Invention) The present invention has been made in view of the above-mentioned problems. In a galvano mirror for tilting and driving a mirror, rigidity in a direction perpendicular to a direction in which a support member extends is increased. It is another object of the present invention to provide a galvanomirror capable of reducing vibration in a direction perpendicular to the direction in which the support member extends.

[0017]

A movable member having at least a reflective surface, a support member for supporting the movable member so as to be tiltable about a first axis and a second axis with respect to a fixed member, and the movable member. In a galvanomirror having first driving means for driving the first axis about the first axis and second driving means for driving the second axis about the second axis, wherein the supporting member comprises the first axis and the second axis. A portion extending on a plane substantially parallel to a plane including the axis and having increased rigidity in a direction perpendicular to a plane including the first axis and the second axis. Thus, it is possible to suppress vibration generated when a force is applied in a direction perpendicular to a plane including the first axis and the second axis.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIGS. 1 to 8 relate to a first embodiment of the present invention, and FIG. 1 shows a schematic configuration of an optical path switching device provided with a second embodiment. 3 is a perspective view of the configuration of the galvanometer mirror, FIG. 3 is an exploded view of the configuration of the galvanometer mirror, FIG. 4 is a view of the galvanometer mirror as viewed from the front, and FIG. 6 shows a cross-sectional structure from the vertical direction, FIG. 7 shows a configuration of an optical system of the tilt sensor cut out in a horizontal plane, and FIG. 8 shows a configuration of an optical system of the tilt sensor cut out in a vertical plane. .

As shown in FIG. 1, the optical path switching device 10 for optical communication employs the galvanomirror 1 of the first embodiment. The light for signal transmission for optical communication emitted from one optical fiber 3 is converted into parallel light by a lens 4 and the incident light 5 is projected on a reflection surface 6 a on the front surface (front surface) of a mirror 6 constituting the galvanometer mirror 1. Then, the light is reflected by the reflecting surface 6a to become reflected light 7.

The mirror 6 is rotatably supported by rotating shafts 8 and 9 in two directions orthogonal to each other. By applying a drive signal to two coils described later, the mirror 6 is rotated with the rotating shaft 8. 9 so that the tilt direction of the reflection surface 6a can be set freely.

The reflected light 7 on the reflecting surface 6a of the mirror 6 is, for example, a total of nine lenses 11-1 arranged in three steps (rows) and three columns on a plane substantially perpendicular to the direction of the reflected light 7. ,
Nine optical fibers selectively incident on one of 11-2,..., 11-9 and arranged on the optical axis of each lens 11-i (i = 1, 2,..., 9). The light is selectively incident on one of the mirrors 12-i (the tilt direction of the reflection surface 6a of the mirror 6 is controlled by the drive signal as described above).

For example, by tilting the mirror 6 around the rotation axis 8, the reflected light 7 from the mirror 6 is deflected in the X direction, which is the horizontal direction in FIG. 1, and by tilting the mirror 6 around the rotation axis 9, 6 is deflected in the Y direction, which is the vertical direction in FIG.
−9, and can be selectively incident on the optical fibers 12-1 to 12-9.

Thus, the optical fiber for outputting light from one optical fiber 3 on the incident side is changed to nine optical fibers 12-.
It is possible to perform optical path switching for selecting and outputting from i. The incident light 5 and the reflected light 7 are main light beams deflected by the mirror 6 of the galvanometer mirror 1. Hereinafter, a specific configuration of the galvanomirror 1 will be described with reference to FIGS.

As shown in FIG. 2, the galvanometer mirror 1 comprises a mirror 6 disposed at the center of a magnet holder 14 attached to a front opening of a housing 13 and having two axes 8, 9 in a vertical direction and a horizontal direction orthogonal to the mirror. A support driving mechanism rotatably supported around the mirror 6 and a rotational displacement of the mirror 6 in two axial directions are arranged in the housing 13 on the back surface side of the mirror 6 (using light in two dimensions or two directions). And a position detecting device.

As shown in FIG. 2 and the like, the mirror 6 has a square (or rectangular) plate shape, and a reflection surface 6a on the front side thereof.
Is coated with a coating film having a high reflectance with respect to a wavelength of 1.5 μm of main light used for optical communication, for example. Further, a coating film is applied to the back surface 6b (see FIG. 3) of the mirror 6 so that the reflectance of, for example, a wavelength of 780 nm of a laser 17 (see FIG. 3) for generating light for a sensor is high.

This mirror 6 is a square frame-shaped mirror holder 1
8 are housed in a mounting recess 18a at the center of the mounting portion 8, and are positioned and fixed around the periphery.

As shown in FIG. 6, the mirror holder 18 includes a first forming portion 19 formed in a rectangular frame on the outside and a second forming portion 20 formed in a substantially rectangular frame on the inside. That is, the mirror 6 is housed and fixed in the front surface of the second molded portion 20. A first formed portion 19 is formed in a stepped shape at a substantially central position in the front-rear direction outside the second formed portion 20, and a second stepped portion adjacent to the first formed portion 19 (a stepped portion thereof) is provided. The first coil 21 and the outer peripheral surface of the molding portion 20
And a function of a coil holder for fixedly holding the second coil 22.

Four springs 23 (see FIG. 5) each having a substantially circular arc shape are arranged at the outer peripheral position of the first molded portion 19, and one end of the spring 23 is attached to the magnet holder 14.
The other end is insert-molded on the mirror holder 18. The spring 23 is insert-molded in the magnet holder 14 and the mirror holder 18.

When the first molded portion 19 of the mirror holder 18 and the magnet holder 14 are molded of plastic, four springs 23 (etching a 20 μm foil of beryllium copper and gold-plated on the surface) are used. The inner part is first insert-molded on the first molded part 19 of the mirror holder 18, and the outer part is first insert-molded on the magnet holder 14,
Its ends are retained.

Next, the first coil 21 and the second coil 22 are insert-molded on the front and rear sides of the spring 23 when the second molding portion 20 is molded, and are fixed to the mirror holder 18. The mirror holder 18 to which the mirror 6 is attached in this way, and the first coil 21 and the second coil 22 attached to the outer peripheral surface of the mirror holder 18 constitute a movable portion, and the movable portion serves as a support member. Are rotatably supported around the rotating shafts 8 and 9.

As shown in FIG. 5A, four springs 23
(Note that, in FIG. 5, the springs are not indicated by reference numeral 23, and reference numerals 23a, 23b,
23c), one end is fixed to each of two positions near the center of the upper surface and the center of the lower surface of the mirror holder 18 near the rotation shaft 8. The vicinity of the fixed end has a first deformed portion 23a which is parallel to the rotation axis 8.

The other end of the spring 23 is connected to the magnet holder 1
The left and right side walls near the rotary shaft 9 are fixed at two places. The other end near the fixed end has a second deformed portion 23b which is made parallel to the rotating shaft 9. In addition,
The second deformed portion 23b passes through a rectangular protruding portion 24 protruding from the left and right side surfaces of the magnet holder 14.

The first deformed portion 23a and the second deformed portion 23b
Are arranged so as to surround the four corners of the mirror holder 18. These four deformed portions 23a,
The spring 23 having the connecting portion 23c and the deformed portion 23b serves as a support member in the present embodiment.

In the vicinity of the first deformed portion 23a, a soldering portion 25 connected to the first deformed portion 23a inside the mirror holder 18 is arranged, and a total of four soldering portions 2 are provided.
5, ends of both ends of the first coil 21 and the second coil 22 are fixed with a conductive adhesive.

The end of the second deformed portion 23b is inserted into the magnet holder 14. The inserted portion passes through the inside of the magnet holder 14 and reaches four terminals 26 projecting to the outer surface of the magnet holder 14. . Power is supplied through the flexible cable by soldering the flexible cable to the four terminals 26, and the two coils 21 and 22 are connected via the four springs 23.
, And a movable signal can be rotated.

Dampers 27 and 28, which are silicon gels having ultraviolet curing properties, are provided so as to adhere to the first deformed portion 23a and the soldering portion 25, and to the second deformed portion 23b and the protruding portion 24. The function of typing with respect to the vibration of both ends of the spring 23 is maintained.

As shown in FIG. 3, FIG. 4, FIG. 6, etc., the two magnets 31 magnetized in the horizontal direction have a yoke 32 adhered to the back surface thereof, and the first coil 21 faces the inside thereof. Magnet holder 14 at both left and right positions
Adhesively fixed. The magnetic circuit forms a magnetic circuit in which the magnetic field generated by the magnet 31 acts on the first coil 21 disposed facing the inside.

Mirror holder 18 and magnet holder 14
Is formed of a non-conductive plastic, for example, a liquid crystal polymer containing whisker titanate. As shown in FIG. 3, the two magnets 33 magnetized in the vertical direction have a yoke 34 adhered to the back surface, and the second coil 22 faces the inside thereof.
4 and fixed. The substantially rectangular frame-shaped magnet holder 14 is adhered to an open front mounting surface 13a of the housing 13 formed by, for example, zinc die casting.

The mirror holder 18 on which the mirror 6 is mounted as described above, the first and second coils 21 and 22 constitute a movable part, and the center of gravity G of the movable part is on the rotating shaft 8 as shown in FIG. And on the rotation shaft 9. The main axis of inertia of the movable part coincides with the rotation axis 8 and the rotation axis 9.

The spring 23 is arranged so as to exist on the plane defined by the rotating shaft 8 and the rotating shaft 9. Further, the first deformed portion 23a shown in FIG. 5A is disposed at a position substantially coincident with the rotating shaft 8, and the second deformed portion 23b is
It is arranged at a position that almost matches.

As shown in FIG. 6, instead of arranging the spring 23 at the center between the first coil 21 and the second coil 22 attached to the front and rear, the first coil having the mirror 6 is arranged.
The spring 23 is arranged at a position near the coil 21 of the above, so that the position of the center of gravity including the mirror 6 can be matched with the rotating shafts 8 and 9 without a balancer.

The force generated in the first coil 21 is generated at the driving point D1 in the vertical direction in the plane of FIG.
As a result, a torque is generated around a midpoint D1-1 connecting both drive points D1 and D1. FIG. 6 shows a cross section taken along a horizontal plane including the rotating shaft 9. The torque around the driving points D1 and D1-1 is on a horizontal plane including the rotating shaft 9.

In the second coil 22, a force is generated on the side in the front and back direction of the drawing in FIG. 6, and the force is generated at the driving point D2 in FIG. 6 on the upper and lower surfaces perpendicular to the drawing in FIG. I do. As a result, a torque is generated around a midpoint D2-1 connecting the two driving points D2, D2 (in FIG. 6, the two points D2, D2 coincide with the point D2-1). In FIG. 8, the driving points D2 and the like are shown separately for easier understanding. FIG.
FIG. 4 shows a perspective view when cut along a vertical plane including the rotation shaft 8;
The torque around the driving points D2 and D2-1 indicates that the torque is on a vertical plane including the rotation axis 8. As shown in FIG. 6, the torque around D1-1 and the torque around D2-1 are formed so as to be close to the center of gravity G.

The housing 13 is provided with a sensor for detecting the inclined surface of the mirror 6 due to the rotation about the rotation shafts 8 and 9. As shown in FIGS. 3 and 7, a laser (diode) 17 as a light source for the sensor is press-fitted into the opening 30b at the rear end of the housing 13 and fixed. The laser light emitted from the laser 17 is located at a position in front of the
PBS having a polarization plane 36a to which a 4λ plate 35 is bonded
The (polarizing beam splitter) 36 has an adhesive surface 36b formed on one side thereof, which is adhesively fixed to the (one) inner wall surface of the housing 13.

A lens 37 is disposed in the housing 13 at a position in front of the PBS 36 and is fixed by bonding. Then, the laser beam from the laser 17 is transmitted to the PBS 36, 1/4.
The light is condensed through the λ plate 35 and the lens 37 and is
The light is incident on the back surface 6 b of the mirror 6 held at 8. In addition, an opening 18b having a circular inner wall shape is formed on the rear surface side of the lens holder 18.
(A)).

As shown in FIG. 7, a position detecting sensor (PSD) 38 for detecting a light irradiation center position of the projected light in two directions is provided so as to face a side surface of the PBS 36 opposite to the bonding surface 36b. It is adhesively fixed to an opening provided on the side surface of the housing 13. The PSD 38 is a two-dimensional position sensor that outputs the center position of the light projected on the light receiving unit 38a in two directions (Y and Z directions) as a voltage. For example, S5990-01 and S7848- of Hamamatsu Photonics KK
01 and the like can be adopted.

The operation of the galvanomirror 1 having such a configuration will be described. When an electric current is applied to the first coil 22 via two of the four springs 23, a torque is generated to rotate around the rotation shaft 8 by a magnetic field received from the magnets 31 arranged on both left and right sides of the first coil 22. The first deformable portion 23a receives the torsional deformation, and inclines (rotates) the movable portion around the rotation shaft 8.

When an electric current is applied to the second coil 21 via the other two of the four springs 23, a torque for rotating around the rotating shaft 9 is generated by a magnetic field received from the magnets 33 arranged on the upper and lower sides of the second coil 21. The second deformable portion 23b is torsionally deformed, and the movable portion is tilted (rotated) around the rotating shaft 9.

The laser light generated by the laser 17 enters the PBS 36 as P-polarized light, transmits almost 100% through the polarization plane 36a, becomes circularly polarized light via the ４λ plate 35, and enters the lens 37. The light is condensed by the lens 37 and enters the back surface 6 b of the mirror 6. The light reflected on the back surface 6b passes through the λλ plate 35, becomes S-polarized light whose polarization plane is rotated by 90 degrees, and is incident on the polarization plane 32a with this S-polarized light. The light is reflected 100% and is incident on the light receiving surface 38a of the PSD 38 in a spot shape.

When the mirror 6 is tilted around the rotation axis 8, the light on the light receiving surface 38a moves in the Z direction in FIGS. 3 and 7, and when the mirror 6 is tilted about the rotation axis 9, the light on the light receiving surface 38a is changed. Moves in the Y direction, the tilt of the mirror 6 in two directions can be detected from the output of the PSD 38. Accordingly, by supplying a drive signal to the first coil 21 and the second coil 22 so that the position detection signal from the PSD 38 has a desired value, the tilt of the mirror 6 (the reflection surface 6a of the mirror 6) is provided together with the movable portion. The angle can be controlled to a desired value.

Next, the main part of this embodiment will be described mainly with reference to FIG. As shown in FIG. 5A, the spring 23 is a surface parallel to the reflection surface of the mirror 6 as a whole, and has two rotating shafts 8.
And a plane parallel to the XY plane, which is also parallel to the plane including the rotation axis 9.

FIG. 5A is a sectional view taken along line AA of FIG.
As shown in (B), the first deformed portion 23a has a cross-sectional size of a thickness t1 of 20 microns, a width w1 of 70 microns, and a large dimension in a direction parallel to the XY plane. Stiffness in the Z direction, which is a direction perpendicular to the XY plane, is high.

The second deformed portion 23b also has the first shape.
This is the same as the deformed portion 23a. That is, the cross-sectional size is such that the thickness t1 is 20 microns, the width w1 is 70 microns,
The dimension in the direction parallel to the XY plane is large,
The rigidity in this direction is high, and the rigidity in the Z direction, which is a direction perpendicular to the XY plane, is low.

FIG. 5A is a sectional view taken along the line BB in FIG.
As shown in (C), a connecting portion 23c (as an intermediate portion connecting the first deformed portion 23a and the second deformed portion 23b)
Is made of beryllium copper in the center, and the first deformed portion 23
a, an inner peripheral portion 23c-1 formed integrally with the second deformed portion 23b by etching, and an outer peripheral portion 23c-2 molded of plastic around the inner peripheral portion 23c-1. Outer part 23c-
2 is formed at the same time when the spring 23 is insert-molded in the magnet holder 14.

As shown in FIG. 5C, the cross section of the connecting portion 23c has a thickness t3 of 400 microns, a width w3 of 200 microns, and a Z direction perpendicular to the XY plane. Is larger, and this Z
The rigidity in the direction is higher than the rigidity in the direction parallel to the XY plane.

The cross-sectional size of the connecting portion 23c is large in both the horizontal direction and the vertical direction with respect to the XY plane in the cross-sectional size of the inner peripheral portion 23c-1, so that the rigidity in both directions is increased. I have. In particular, since w3 / w2 <t3 / t2, the rigidity in the direction perpendicular to the XY plane is particularly increased.

The inner peripheral portion 23c of the connecting portion 23c-
No. 1 has a thickness t2 of 20 microns and a width w2 of 100 microns, and, like the first deformed portion 23a, has a large dimension in a direction parallel to the XY plane, and has a high rigidity in this direction. , The rigidity in the Z direction, which is the direction perpendicular to the XY plane, is low.

When there is no outer peripheral portion 23c-2, the spring 23
From the fixed end on the mirror holder 18 side to the fixed end on the magnet holder 14 side, the dimension in the direction parallel to the XY plane is large, the rigidity in this direction is high, and The rigidity in the Z direction, which is the direction, is reduced.

Since the spring 23 is formed by etching beryllium copper having a thickness of 20 microns, the width of the spring 23 in the etching direction can be reduced only to about twice the thickness. On the other hand, it is difficult to make the dimension in the Z direction, which is the vertical direction, larger than the width.

For this reason, in the present embodiment, the outer peripheral portion 2 made of plastic is formed at the connecting portion 23c of the spring 23.
By adding 3c-2, the rigidity of the spring 23 in the thickness direction can be increased. Also, since both a portion having high rigidity in the direction perpendicular to the plane on which the spring 23 extends and a portion having high rigidity in the direction parallel to the spring 23 are formed, the spring 23
The rigidity can be increased in a well-balanced manner both in the direction parallel to the plane in which it extends and in the direction perpendicular thereto.

With the above configuration, vibration in the Z direction
Even in the case where there is resonance, the vibration can be reduced because the rigidity of the connecting portion 23c, which is the intermediate portion of the spring 23, is high, and the vibration of the mirror 6 can be reduced. Can be stabilized.

This embodiment has the following effects.

In a galvano mirror that tilts the mirror 6 as an optical element around two axes, two kinds of coils 21 and 22 that are integrally formed with the mirror 6 and tilt in two directions are support members. The spring 23 including the rotation center is disposed so as to be sandwiched in a direction perpendicular to the reflection surface of the mirror 6. Therefore, it can be set so that the center of the driving torque of the coils 21 and 22 does not largely deviate from the support member and the rotation center.

Further, the position of the center of gravity of the movable portion including the two types of coils 21 and 22 can be easily matched with the center of rotation. Therefore, in the drive characteristic of the inclination of the mirror 6,
The occurrence of resonance can be suppressed, and the servo characteristics can be improved.

The coils 21 and 22 inclined in two directions are arranged on both sides of the support member, and are separated from the reflecting surface 6a of the mirror 6 in the vertical direction. Therefore, two coils 21,
22 and magnets 31, each of which is a magnetic circuit,
33 can be easily arranged without interference. Further, with such an arrangement, even if the two coils 21 and 22 are separated from each other in the direction perpendicular to the reflection surface 6a of the mirror 6, the deviation from the support point can be reduced. Therefore, magnet 3 for two-way rotation
1, 33 can be easily arranged, and the mutual magnetic interference between the two rotating magnets 31, 33 can be reduced.
The disturbance of the magnetic field acting on the two coils 21 and 22 can be reduced.

Since there are four springs 23, the coils 21 and 22 driven in two directions can also serve as a total of four power supply lines (drive lines) of +/-. This eliminates the need for a flexible cable or the like for supplying power to the movable unit, and does not affect the operation of supporting and driving the mirror 6.

Further, since the damping members are disposed at both ends of the spring 23, the vibration generated when the spring 23 is torsionally deformed can be effectively suppressed. Further, the inclination sensor of the mirror 6 is arranged in a direction on the back side of the reflection surface 6a for the main light beam. Therefore, it is possible to prevent the inclination sensor from interfering with the main light beam.

Further, in this embodiment, an outer peripheral portion 23c-2 is provided at a connecting portion 23c connecting the first deformed portion 23a and the second deformed portion 23b near the rotating shafts 8 and 9, and the outer peripheral portion 23c-2 is provided. The stiffness is defined as the stiffness in the direction perpendicular to the plane including the rotation axes 8 and 9 (from the value of the stiffness in the direction parallel to the plane).
Since the support member is enlarged, unnecessary vibration in a direction perpendicular to the plane on which the support member extends can be suppressed.

Therefore, when a force in the direction perpendicular to this plane acts, the vibration of the mirror 6 can be reduced quickly, and the light reflected by the mirror 6 can be stabilized. In other words, even when the movable part is driven to rotate, the movable part can be quickly returned to the initial state, and the response characteristics can be improved. Alternatively, unnecessary vibration of the movable portion can be suppressed, and an effect that high-precision light deflection control can be achieved.

Note that, instead of the mirror 6, a prism, a lens, a composite optical element thereof, or another optical element may be used. In addition, instead of the PSD 38, in the YZ directions of FIG.
A quadrant photodetector (PD) may be used. Alternatively, another tilt sensor may be used. In the present embodiment,
Although described for optical communication, the present invention can be applied to an optical deflector used for a measuring instrument, a pickup for optical recording, and the like.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 9 shows the structure around the inner support member in the second embodiment. This embodiment differs from the first embodiment only in the configuration of the spring 23. Therefore, different components will be described below. Others are the same as the first embodiment.

First deformed portion 23 in the present embodiment
a, the second deformed portion 23b has the same configuration as that of the first embodiment. That is, as shown in FIG. 9B of the A′-A ′ cross section of FIG. 9A, the first deformed portion 23a has a thickness t1 of 20 μm and a width w1 of 70 μm and has a cross-sectional shape. The first deformed portion 23a is shown in FIG.
Is the same as

In this embodiment, FIGS. 9A and 9
As shown in FIG. 9C (of the cross section B′-B ′ in FIG. 9A), a bent portion 23c-3 is formed in the connecting portion 23c, for example, at a portion near the second deformed portion 23b.

By providing the bent portion 23c-3, the thickness t3 (a dimension in the Z direction perpendicular to the XY plane from the XY plane) of the spring 23 can be increased. In this case, the thickness is set to 400 microns. . The thickness t2 and width w2 shown in FIG. 9B are the same as those in the first embodiment (specifically, the thickness t2 is 20 microns and the width w2 is 100 microns).

As described above, the bent portion 2 is connected to the connecting portion 23c.
By providing 3c-3 (or a bent portion or a standing portion extending from the XY plane in the Z direction), the dimension in the Z direction can be partially increased, and the rigidity in that direction can be increased. Other configurations are the same as those of the first embodiment.

In the present embodiment, the bent portion 23c-
Since 3 is a thin metal, the mass of the connecting portion 23c can be made smaller than in the first embodiment. The present embodiment has substantially the same effect as the first embodiment, and also includes a portion of the connecting portion 23c (a portion formed in advance by wide etching or the like).
Can be formed simply by bending, so that the rigidity in the Z direction can be increased more simply and at lower cost than in the first embodiment.

In FIG. 9A, the bent portion 23c-
Although 3 is provided in a part of the connecting portion 23c, it is not limited to this, and may be formed over the entire length of the connecting portion 23c. Further, in the above-described case, the bent portion 23c-3 is formed such that it is bent at 90 degrees from one end of the connecting portion 23c. However, another bent angle such as 30 degrees may be used. Also, as shown in FIG. 9C, the same effect can be obtained by forming a projecting portion 23c-4 projecting in an arc shape at the center, for example.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 10 is a front view showing a configuration of a spring according to the third embodiment, and FIG. 11 is a perspective view showing a part of FIG. The spring 41 in the present embodiment is formed by etching and bending a beryllium copper having a thickness of, for example, 20 microns.

As shown in FIG. 10, a movable portion 41d for fixing a mirror to the surface of the spring 41 is formed in the center of the spring 41, and a connecting portion 41c arranged in a square frame around the movable portion 41d. Are arranged, and the movable portion 41d and the connecting portion 4
1c are connected to each other by first deformed portions 41a provided at two upper and lower portions along the direction of the rotation shaft 8.

As shown in FIG. 11, the first deformed portion 41a has a portion connecting the movable portion 41d and the connecting portion 41c.
It is formed by being bent by 0 degrees, and is erected from the XY plane in the Z direction perpendicular to this plane to increase the rigidity in the Z direction. Similarly, the connecting portion 41c and the fixed portion 41e disposed around the connecting portion 41c are connected by second deforming portions 41b provided at two places on the left and right along the direction of the rotating shaft 9, and this second deforming is performed. The portion 41b is also formed by bending by 90 degrees, and is erected from the XY plane in the Z direction perpendicular to this plane to increase rigidity in the Z direction.

As described above, the first deformed portion 41a and the second deformed portion 41b are formed along the rotating shafts 8 and 9, respectively, so that the mirror can be freely rotated around the rotating shafts 8 and 9. It is designed to hold. The coils are arranged on both surfaces of the movable portion 41d in the same manner as in the first embodiment. Further, a thin film of polyimide is formed on the surface of the spring 41, a copper pattern is formed thereon, and power is supplied from the fixed portion 41e to the movable portion 41d.

The first deformed portion 41a, the second deformed portion 41b
Is bent 90 degrees, the dimension of the cross-sectional area of this portion in the Z direction can be made larger than that in the XY directions, and the rigidity in the Z direction can be increased. Therefore, the present embodiment has the same effect as the first embodiment.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIGS.
FIG. 12 is an exploded view showing a configuration of a main part of a galvanometer mirror according to a fourth embodiment. FIG. 13 shows a state viewed from the front side. FIG. 14 shows a cross-sectional structure taken along a horizontal plane in FIG. FIG. 15 shows a cross-sectional structure in a vertical plane, and FIG.
Indicates a cross-sectional structure of the first deformed portion and the connecting portion.

The galvanomirror 50 (excluding the sensor portion) shown in FIG.
A silicon substrate of about 00 microns is etched to form a frame 51, a mirror 52, a spring 53 (the mirror 53 is a first
(Consisting of a deformed portion 53a, a second deformed portion 53b, and a connecting portion 53c). The size (size) of the mirror 52 is, for example, 1 mm × 1 mm.

On both sides of a square or rectangular plate-like mirror 52 formed at the center of the frame 51, two first magnets 54 and two second magnets 55 are respectively provided in parallel in the vertical and horizontal directions. It is fixed.

[0086] Both sides of the frame 51 are
The first coil 56 and the second coil 57 are fixed via spacers 58 and 59, respectively. The spring 53 is connected to the center mirror 52, is connected to the frame 51 and has a first deformed portion 53 a formed at two locations in the vertical direction along the rotation axis 8, and is connected to the frame 51 and has two horizontal deformations along the rotation axis 9. It has a second deformed portion 53b formed at a location and a square or rectangular frame-shaped connecting portion 53c connecting these.

The first deformed portion 53a rotatably supports the mirror 52 having the magnets 54 and 55 attached to both sides thereof around the rotating shaft 8, and the second deformed portion 53b around the rotating shaft 9. A mirror 52 having magnets 54 and 55 attached to both sides is rotatably supported. Then, as shown in FIG. 13, the incident light 5 is reflected by the front surface of the mirror 52, and the reflected light 7 is guided to the fiber 12-i (see FIG. 1).

In the present embodiment, unlike the first embodiment, the magnets 54 and 55 are arranged on the movable part and the coils 56 and 57 are arranged on the fixed part side. There is no need to route the power supply line. Therefore, the four springs 53 have a connected shape, and one of the first deformed portion 53a and the second deformed portion 53b is arranged on each of the upper, lower, left and right sides of the mirror 52.

As shown in FIGS. 14 and 15, the first magnet 54 faces one side inside (in the left-right direction) of the first coil 56, and the second magnet 55
7 (in the vertical direction). When a current flows through the first coil 56, the first magnet 54 receives a force, and the movable portion rotates around the rotation axis 8. When an electric current is applied to the second coil 57, the second magnet 55
Receives the force, and the movable part rotates around the rotation axis 9.

Further, in the present embodiment, the first deformed portion 5
A plurality of concave portions 53d are formed on both surfaces of a connecting portion 53c connecting the 3a and the second deformed portion 53b. FIG.
As shown in FIG. 6A, the cross-sectional shape of the first deformed portion 53a is rectangular, the width w1 in the X direction is 10 microns,
The thickness t1 in the Z direction is set to 100 microns, the thickness is made larger than the width, and the aspect ratio is made larger. This allows a polysilicon substrate to be formed by anisotropic etching.

Further, as shown in FIG.
3c is provided with a plurality of concave portions 53d from both sides thereof, so that the cross-sectional shape thereof is formed in an H-shape.
Even if the cross-sectional outer shape of the is increased, the weight is reduced and the rigidity is increased. The cross-sectional size of the connecting portion 53c is such that the thickness t2 is 100 microns, which is the same as the thickness t1, and the width w2
Is greater than the thickness t2 as 150 microns.
The depth of the concave portion 53d is set to several tens of microns, and the thickness t4 of the concave portion 53d is also set to about several tens of microns.

Therefore, the moment of inertia in the rotational direction when the connecting portion 53c simultaneously rotates with the movable portion around the rotating shaft 9 can be reduced, and the driving sensitivity in this direction can be increased. Other configurations are the same as those of the first embodiment.

In the present embodiment, the first deformed portion 53a and the second deformed portion 53a are formed by etching using a silicon substrate having a larger thickness than that of the first embodiment.
The cross-sectional shape of the deformed portion 53b is
The size in the plane direction is larger than the size in the Z direction perpendicular to this plane, and the rigidity in the XY plane is increased.

For this reason, by adjusting the width of the connecting portion 53c in the XY plane, the rigidity in the direction perpendicular to the plane can be sufficiently increased. For this reason, in the present embodiment, the connecting portion 53c is provided with the concave portion 53d so as to be thin and secure the required rigidity with light weight.

This embodiment has the following effects. Magnets 54 and 55, which are two kinds of magnetic members for tilting and driving the mirror 52 in two directions, are arranged on both sides of the mirror 52 in the left-right direction and the up-down direction, respectively, and sandwich the center of gravity of the mirror 52 and the movable part. In addition, since the springs 53a and 53b, which are support members, are sandwiched between two types of magnetic members, the center of gravity of the movable portion and the support point can be easily matched, and the drive point and the support point in two directions can be set. The deviation can be reduced.

Therefore, the occurrence of resonance when the movable portion is driven can be suppressed, and the servo characteristics can be improved. Also,
Since the configuration is completely symmetrical with respect to the support point, there is also an effect that a balancer is not required. In addition, since magnets that are driven in two directions are arranged on the movable part, power supply to the movable part is not required.

Further, since it is possible to secure an interval between the two types of coils 56 and 57 disposed on the fixed portion side, the two types of coils 56 and 57 can be easily arranged. Further, by etching a thick substrate, rigidity in a direction perpendicular to a plane including the rotating shafts 8 and 9 can be increased, and unnecessary vibration can be suppressed.

[Supplementary Notes] A movable portion having at least a reflective surface, supporting means for supporting the movable portion to be tiltable around a first axis and a second axis with respect to a fixed member, and driving the movable portion around the first axis A galvanomirror having a first driving unit for driving around the second axis and a second driving unit for driving around the second axis.
The support means extends on a plane substantially parallel to a plane including the first axis and the second axis, and a cross section of the support means is elongated in a direction substantially parallel to the plane. A galvanomirror having a first cross section and a second cross section that is elongated in a direction substantially perpendicular to the plane.

2. 2. The galvanomirror according to claim 1, wherein a thickness of the second section is reduced. 3. 2. The galvanomirror according to claim 1, wherein a reinforcing member is attached to the second cross section to the first cross section.

[0100]

As described above, according to the present invention, in the galvano mirror for tilting and driving the mirror, the rigidity in the direction perpendicular to the direction in which the supporting member extends is increased, so that the direction in which the supporting member extends. Vibration generated when a force is applied in a direction perpendicular to the mirror can be suppressed, and light reflected by the mirror can be stabilized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an optical path switching device provided with a first embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a galvanomirror according to the first embodiment of the present invention.

FIG. 3 is an exploded view showing a configuration of a galvanomirror.

FIG. 4 is a view of a galvanomirror viewed from the front.

FIG. 5 is a diagram showing a structure inside a mirror in FIG. 4;

FIG. 6 is a plan sectional view showing a sectional structure from a vertical direction.

FIG. 7 is a perspective view showing a configuration of an optical system of a tilt sensor cut out in a horizontal plane.

FIG. 8 is a perspective view showing a configuration of an optical system of a tilt sensor cut out in a vertical plane.

FIG. 9 is a diagram illustrating a configuration of a peripheral portion of a support member and the like according to a second embodiment of the present invention.

FIG. 10 is a front view showing a configuration of a spring according to a third embodiment of the present invention.

FIG. 11 is an enlarged perspective view showing a part of FIG. 10;

FIG. 12 is an exploded perspective view showing a configuration of a main part of a galvanometer mirror according to a fourth embodiment of the present invention.

FIG. 13 is a perspective view showing the structure on the front side of the mirror in FIG. 12;

FIG. 14 is a plan sectional view showing a configuration of a main part of the galvanometer mirror.

FIG. 15 is a side sectional view showing a configuration of a main part of the galvanomirror.

FIG. 16 is a cross-sectional view illustrating a cross-sectional structure of a first deformed portion and a connecting portion.

FIG. 17 is a perspective view showing a galvanomirror of a conventional example.

FIG. 18 is a perspective view showing the structure of another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Galvano mirror 6 ... Mirror 8, 9 ... Rotation axis 13 ... Housing 14 ... Magnet holder 17 ... Laser 18 ... Mirror holder 19 ... 1st shaping | molding part 20 ... 2nd shaping | molding 21 ... 1st coil 22 ... 2nd Coil 23 Spring 23a First deformed portion 23b Second deformed portion 23c Connecting portion 23c-1 Inner peripheral portion 23c-2 Outer peripheral portion 25 Soldering portion 26 Terminal 27, 28 ... Dampers 31, 33 ... Magnets 32, 34 ... Yoke 36 ... PBS 38 ... PSD

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C362 BA17 BA18 DA17 2H041 AA12 AB14 AC05 AZ01 AZ08 2H043 CA07 CD03 2H045 AB10 AB13 AB18 BA12 DA02 5D118 AA12 DC07 EA02 EA03 EB02 EC05 ED01 FA13

Claims (5)

[Claims] A movable member having at least a reflection surface; a support member for supporting the movable member so as to be tiltable around a first axis and a second axis with respect to a fixed member; A galvanomirror having first driving means for driving about a second axis and second driving means for driving about the second axis, wherein the support member includes the first axis and the second axis A portion extending on a plane substantially parallel to the plane and having increased rigidity in a direction perpendicular to a plane including the first axis and the second axis is provided. Galvanometer mirror to do. 2. The galvanometer according to claim 1, wherein the portion has an increased rigidity in a direction perpendicular to a plane including the first axis and the second axis by adding a reinforcing member. mirror. 3. The galvanomirror according to claim 1, wherein the support member is formed by processing a thin plate, and the portion is formed by a bent portion. 4. The galvanomirror according to claim 1, wherein the support member has a function of a signal line for supplying a drive signal to two coils provided in the movable section. 5. A movable part having at least a reflecting surface, supporting means for supporting the movable part so as to be tiltable around a first axis and a second axis with respect to a fixed member, and In a galvanomirror having first driving means for driving about an axis and second driving means for driving about the second axis, the supporting means has a thin plate shape, and at least a part thereof is bent. A galvanomirror comprising a portion having increased rigidity in a direction perpendicular to a plane including the first axis and the second axis.