JP2002189188A - Planar type galvanomirror - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a planar type galvanomirror which is arranged with a semiconductor substrate at a center with respect to permanent magnets making a pair in order to act magnetic fields on plane coils of movable sections and enables to prevent the degradation in the reflectivity of a reflecting mirror, reduction of the number of components and improvement in productivity. SOLUTION: The flat planar movable sections 17 and 18 torsion bars 19 and 20 which pivot the movable sections oscillatably with a semiconductor substrate 16 are integrally formed on the semiconductor substrate and the top surfaces of the movable sections 17 and 18 are provided with the plane coils 21. The semiconductor substrate 16 is directly mounted on a base substrate 23 and is fixed by adhesion. The permanent magnets 31 making a pair for acting the magnetic fields on the plane coils of the movable sections are passed through holes 27 and are arranged and fixed at the inner walls of yokes 32. Pattern sections 23a disposed at the base substrate and pattern sections 16a formed on the semiconductor substrate are electrically connected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar galvano mirror used for a laser scanner or an optical switch for deflecting and scanning a laser beam, for example.

[0002]

2. Description of the Related Art A planar type galvanometer mirror is used for a laser scanner or the like that deflects and scans a laser beam. The principle is that when a current is applied to a movable coil disposed in a magnetic field, the current and the magnetic flux are related. It utilizes the fact that an electromagnetic force is generated and a rotational force proportional to the current is generated. The movable coil rotates to an angle where the rotational force and the spring force of the movable coil holding member are balanced, and the pointer is swung through this movable coil to detect the presence or absence and magnitude of the current, using a galvanometer. A mirror (reflecting mirror) is provided instead of the pointer on a shaft (movable coil holding member) that rotates integrally with the coil. A small-sized galvanomirror using a semiconductor has been proposed.

FIG. 1 is a view showing a conventional planar type two-dimensional galvanometer mirror, in which (a) is a top view and (b) is a side sectional view. 2A and 2B are views showing a state in which a silicon substrate is arranged on a pedestal substrate, wherein FIG. 2A is a top view and FIG. 2B is a side sectional view. The movable portion is formed integrally with the silicon substrate 1, and has a frame-shaped outer movable plate 2 supported by the silicon substrate 1 with the first torsion bars 4, 4.
And an inner movable plate 3 axially supported inside the outer movable plate 2 by second torsion bars 5, 5 whose axial direction is orthogonal to
A planar coil 6 is provided on the upper surfaces of the outer movable plate 2 and the inner movable plate 3.
And a reflection mirror 7 is provided on the lower surface of the inner movable plate 3. The silicon substrate 1 is arranged and fixed on a pedestal substrate 8 having a concave shape, and a pattern 1a is provided on the silicon substrate 1;
The pattern 1 a and the wiring pattern 8 a on the pedestal substrate 8 are connected by wires 9. At the bottom of the concave shape of the pedestal substrate 8, a window 10 for laser incident / reflection is opened.

The pedestal substrate 8 is provided with four side through holes 8b, each of which is connected to the wiring pattern 8a. The arrangement and fixing and connection of the pedestal substrate 8 to the base substrate 11 are performed by fixing and connecting the wiring pattern 11a provided on the base substrate 11 and the side through holes 8b of the pedestal substrate 8 by soldering.
An externally input connector 12 is connected to a wiring pattern 11 a on the base substrate 11.

A pair of permanent magnets 13, 13 for applying a magnetic field to the planar coil 6 of the movable portion is provided on the base substrate 11 in parallel with the axial direction of the first and second torsion bars 4, 4, 5, 5. The permanent magnets 13 are arranged and fixed on the lower surface with an adhesive or the like, and the permanent magnets 13 are arranged and fixed on the inner wall of a yoke 14 which is hollowed out in a square shape. Two round holes 15 on the base substrate 11 are provided for fixing screws of a planar type two-dimensional galvanometer mirror.

[0006]

SUMMARY OF THE INVENTION Conventional planar type 2
In the case of the two-dimensional galvanomirror structure, in order to effectively apply the magnetic field of the permanent magnet to the planar coil on the movable part, the concave base member is arranged and fixed so that the semiconductor substrate is arranged at the center of the permanent magnet. The pedestal substrate is fixed to the base substrate. However, in the work of fixing and connecting the pedestal substrate and the base substrate by soldering, the solder flux scatters from the window for entering and reflecting the laser opened on the pedestal substrate and adheres to the reflection mirror provided on the semiconductor substrate. And the reflectivity of the reflection mirror is reduced. In addition, since the soldering operation is performed while adjusting the relative positions of the pedestal substrate and the base substrate, the operation time is extremely long, and the productivity is poor.

Each of the permanent magnets disposed on the upper and lower surfaces of the base substrate has one
The part serves as a permanent magnet. However, since one permanent magnet is divided by the base substrate, the distance corresponding to the thickness of the base substrate reduces the magnetic force generated from the permanent magnet. In addition, it is difficult to arrange the semiconductor substrate at the ideal center of the permanent magnet.

[0008]

A flat movable portion and a torsion bar for pivotally supporting the movable portion with respect to the semiconductor substrate are integrally formed on a semiconductor substrate, and an upper surface of the movable portion is provided on an upper surface of the movable portion. A plane coil and a reflection mirror are provided on the lower surface, and the semiconductor substrate is mounted on a base substrate. A yoke is arranged and fixed on the upper and lower surfaces of the base substrate, and a pair of permanent magnets for applying a magnetic field to a planar coil of a movable portion arranged in parallel with the axial direction of the torsion bar of the semiconductor substrate is provided on the base substrate. It penetrates the drilled hole and is fixed on the inner wall of the yoke.
A planar type galvano mirror in which a pattern portion provided on the base substrate and a pattern portion formed on the semiconductor substrate are electrically connected.

The movable portion has a frame-shaped outer movable plate pivotally supported by the semiconductor substrate with a first torsion bar, and a second torsion bar whose axial direction is orthogonal to the first torsion bar inside the outer movable plate. It consists of an inner movable plate that is pivotally supported by, and a planar coil is provided on the upper surface of the outer movable plate and the inner movable plate,
A reflection mirror is provided on the lower surface of the inner movable plate, and the first and second mirrors are provided.
A pair of permanent magnets for applying a magnetic field to the planar coil of the movable portion arranged in parallel with the axial direction of the torsion bar is fixed to the yoke, and the yoke is a planar galvanomirror arranged on the base substrate.

A planar type galvanomirror is constructed so that a pair of permanent magnets for applying a magnetic field to a planar coil of a movable portion is penetrated through a base substrate having a hole for penetrating the permanent magnets.

A semiconductor substrate is directly adhered and fixed to a base substrate, and a permanent magnet penetrating the base substrate is a planar galvano mirror in which the semiconductor substrate is disposed at the center in the penetrating direction.

[0012]

FIG. 3 is a perspective view of a planar type two-dimensional galvanometer mirror according to an embodiment of the present invention, as viewed from a reflection mirror side. 4A and 4B show the planar type two-dimensional galvanometer mirror shown in FIG. 3, wherein FIG. 4A is a top view, FIG. 4B is a side sectional view, and FIG. 4C is a front sectional view. On the semiconductor substrate 16,
A frame-shaped outer movable plate 17 in which a plate-shaped movable portion is supported by the semiconductor substrate 16 by first torsion bars 19;
The first torsion bars 19, 19 and the second torsion bars 20, 20 whose axial directions are orthogonal to each other, are comprised of an inner movable plate 18 supported inside the outer movable plate 17, and the outer movable plate 17 and the inner movable plate A planar coil 21 is provided on the upper surface of the movable member 18, and a reflection mirror 22 is provided on a lower surface of the inner movable plate 18.

The semiconductor substrate 16 is mounted on the upper surface of the base substrate 23 and fixed by an adhesive or the like. On the semiconductor substrate 16, a pattern 16a is formed.
a and a wiring pattern 23a on the upper surface of the base substrate 23 are connected by a wire 24, and a connector 25 input externally is connected to the wiring pattern 23a.

The base substrate 23 has a hole 26 for allowing a laser to enter and reflect a reflection mirror 22 provided on the lower surface of the inner movable plate 18 of the semiconductor substrate 16, and first and second torsion bars 19, 19, 20, 20. Permanent magnet 31 in the axial direction of
Two through holes 27 are drilled. Also,
Two holes 28 for determining the arrangement position of the yoke 32
And two screw holes 29 and two positioning holes 30 for positioning and fixing the planar type two-dimensional galvanomirror of the present invention.

The yoke 32 is hollowed out in a square shape, and is fixed to the upper and lower peripheral surfaces of the base substrate 23 so as to match the holes 28 for positioning the yoke 32 of the base substrate 23. A pair of permanent magnets 31 for applying a magnetic field to the planar coils 21 of the outer and inner movable plates 17 and 18 are connected to the first and second torsion bars 1 opened on the base substrate 23.
9, 19, 20, and 20 penetrate through the holes 27 for penetrating the permanent magnet 31 in the axial direction, and are arranged and fixed to the inner wall of the yoke 32. Permanent magnet 31 penetrating base substrate 23
Is a position where the semiconductor substrate 16 is arranged at the center of the permanent magnet 31 with respect to the penetration direction.

[0016]

As described above, since the semiconductor substrate is directly bonded and fixed to the base substrate, the pedestal substrate becomes unnecessary, and the number of components can be reduced.

Since the semiconductor substrate is directly adhered and fixed to the base substrate, a reduction in the reflectance of the reflection mirror due to the absence of soldering work around the reflection mirror provided on the semiconductor substrate is prevented and production is performed. Performance can be improved.

By forming a hole in the base substrate through which the permanent magnet penetrates, a pair of permanent magnets for applying a magnetic field is not divided by the base substrate, so that a reduction in magnetic force can be prevented.

By forming a hole for penetrating the permanent magnet in the base substrate, it becomes possible to arrange the semiconductor substrate at the center, which is an ideal position of the penetrated permanent magnet.

[Brief description of the drawings]

FIG. 1 is a view showing a conventional planar type two-dimensional galvanometer mirror, where (a) is a top view and (b) is a side sectional view.

FIG. 2 is a view showing a state in which a silicon substrate of a conventional planar type two-dimensional galvanometer mirror is arranged on a pedestal substrate;
(A) is a top view, (b) is a side sectional view.

FIG. 3 is a perspective view of a planar type two-dimensional galvanometer mirror according to an embodiment of the present invention, as viewed from a reflection mirror side.

4A and 4B are planer type two-dimensional galvanometer mirrors shown in FIG. 3, wherein FIG. 4A is a top view and FIG.

[Explanation of symbols]

 Reference Signs List 1 silicon substrate 1a pattern 2 outer movable plate 3 inner movable plate 4 first torsion bar 5 second torsion bar 6 planar coil 7 reflection mirror 8 pedestal substrate 8a wiring pattern 8b side through hole 9 wire 10 window 11 base substrate 11a wiring pattern 12 Connector 13 Permanent magnet 14 Yoke 15 Round hole 16 Semiconductor substrate 16a pattern 17 Outer movable plate 18 Inner movable plate 19 First torsion bar 20 Second torsion bar 21 Flat coil 22 Reflection mirror 23 Base substrate 23a Wiring pattern 24 Wire 25 Connector 26 Hole 27 hole 28 hole 29 screw hole 30 positioning hole 31 permanent magnet 32 yoke

Claims (4)

[Claims] 1. A semiconductor substrate in which a plate-shaped movable portion and a torsion bar for pivotally supporting the movable portion with respect to the semiconductor substrate are integrally formed, a planar coil is provided on an upper surface of the movable portion, and a lower surface is provided on the lower surface. Is provided with a reflection mirror, the semiconductor substrate is mounted on a base substrate, and a pair for applying a magnetic field to the base substrate and a planar coil of a movable portion disposed in parallel with the axial direction of the torsion bar of the semiconductor substrate. A planar galvano mirror in which a permanent magnet to be formed is fixed to a yoke, the yoke is arranged and fixed to a base substrate, and a pattern portion provided on the base substrate and a pattern portion provided on the semiconductor substrate are electrically connected. A movable portion having a frame-shaped outer movable plate pivotally supported by the semiconductor substrate with a first torsion bar; and a second torsion bar having an axial direction orthogonal to the first torsion bar. It consists of an inner movable plate that is pivotally supported inside, and a planar coil is provided on the upper surface of the outer movable plate and the inner movable plate,
A reflection mirror is provided on the lower surface of the inner movable plate, and the first and second mirrors are provided.
A planar galvano mirror in which a pair of permanent magnets for applying a magnetic field to a plane coil of a movable portion arranged in parallel with the axial direction of a torsion bar is fixed to a yoke, and the yoke is arranged on a base substrate. 3. The structure according to claim 1, wherein a pair of permanent magnets for applying a magnetic field to the planar coil of the movable portion is penetrated through the base substrate having a hole for penetration. Planar type galvanometer mirror. 4. The planar galvanomirror according to claim 3, wherein the semiconductor substrate is directly adhered and fixed to the base substrate, and the semiconductor substrate is disposed at the center of the permanent magnet penetrating the base substrate in the penetrating direction. .