JP2009294425A - Optical scanner device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical scanner device capable of joining a mirror device and a support substrate mutually and accurately to prevent their positions from being deviated. <P>SOLUTION: In this optical scanner device, recessed parts 61a, 61b are formed a substrate 2 which are provided with a mass part 21 having a light reflection part 213, supporting parts 24, 25 for supporting the mass part 21, and connection parts 22, 23 connecting the mass part 21 with the supporting parts 24, 25 turnably and provided with an elastic part. Projecting parts 63 to be fitted into the recessed parts 61a, 61b are formed on a support substrate 3 joined with the substrate 2 and supporting the substrate 2, and the projecting parts 63 are formed by arranging ball-shaped soldering alloys. A metallic film 62 is formed on a surface of the recessed part 61a, and the recessed part 61a and the projecting part 63 are fixed by joining the metallic film 62 in the recessed part 61a and the projecting part 63 mutually by soldering. On the other hand, the projecting part 63 is fitted into the recessed part 61b, but they are not fixed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical scanner device and an image forming apparatus.

  In an optical deflector intended to be applied to a display, a printer, or the like that performs image drawing using laser light, further speeding up of optical scanning is required in order to increase the resolution of the image. However, there is a limit to improving the performance of polygon mirrors and galvanometer mirrors that are currently used, and mirror devices manufactured by processing silicon substrates with MEMS (Micro Electro Mechanical System) are expected as optical deflectors to replace them. ing. Since such a MEMS mirror can be driven at a higher resonance frequency than a polygon mirror or a galvanometer mirror, an image with higher resolution can be formed.

  In general, a mirror device formed of a silicon substrate is bonded to a base or a support substrate for wiring extraction. In this case, it is necessary to bond the mirror device and the support substrate with high precision so as not to shift the bonding position.

  For example, in the optical scanning device described in Patent Document 1, a through electrode is provided on a base substrate bonded to a mirror substrate, and a driving voltage for driving the mirror can be applied from the outside through the through electrode. Like that.

Further, in the optical scanning device described in Patent Document 2, the external electrodes of the drive electrodes on the base substrate formed in the same direction are formed at the same height, and the electrodes and devices on the base substrate are formed by solder balls or the like. It is joined.
JP 2004-109651 A JP 2005-257944 A

However, the method described in Patent Document 1 requires that a through electrode be provided on the cover substrate, which complicates the manufacturing process and limits the material for forming the cover substrate to insulating materials.
In the method described in Patent Document 2, a mechanism for alignment needs to be provided separately.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical scanner device and an image forming apparatus that can be accurately joined with a simple mechanism so that the positions of a mirror device and a support substrate do not shift.

  An optical scanner device according to the present invention includes a mass part having a light reflecting part having light reflectivity, a support part for supporting the mass part, and the mass part rotatably connected to the support part. And an optical scanner that scans light reflected by the light reflecting portion onto an object by rotating the mass portion while twisting and deforming the elastic portion. An apparatus, comprising: a first substrate including the mass unit, the support unit, and the connecting unit; and a second substrate bonded to the first substrate and supporting the first substrate. A concave portion is formed on one of the first substrate and the second substrate, and a convex portion that fits on the concave portion is formed on the other.

  According to the present invention, by fitting the concave portion and the convex portion, it is possible to accurately join the first substrate and the second substrate with a simple mechanism so that the positions of the first substrate and the second substrate do not shift.

  Further, the support portion of the first substrate is provided with the concave portion, the second substrate is provided with the convex portion, and a metal film is formed on the surface of the concave portion. Preferably, the convex portion is formed of a metal material that can be bonded to the metal film, and the concave portion and the convex portion are metal bonded.

Thereby, when manufacturing a 1st board | substrate, since a recessed part can be produced together, it is not necessary to increase a manufacturing process. Further, since the convex portion on the second substrate can be formed by arranging a metal material in a protruding shape, it is not necessary to process the second substrate itself, so that the manufacturing process is simple, and the second substrate Can be formed of a material that is difficult to process.
In addition, the said convex part can be formed with a metal bump or a solder alloy, for example.

  In addition, a second recess is formed on one side of the first substrate and the second substrate on the opposite side of the recess with the mass portion in between, and the rotation axis of the mass portion is on the other side. In the direction, a second convex portion is formed on the opposite side of the convex portion across the mass portion, the convex portion is fixed to the concave portion, and the second convex portion is fitted into the second concave portion. It is desirable that

  In this way, by fixing only one side across the mass part in the direction of the rotation center axis of the mass part, it is possible to relieve stress generated due to the influence of heat or the like during driving of the mass part.

  An image forming apparatus according to the present invention is an image forming apparatus provided with the above-described optical scanner device, and scans the light reflected by the light reflecting unit by rotating the mass unit, and thereby on the object. An image is formed on the screen.

  According to the present invention, since the concave portion and the convex portion are fitted, it is possible to accurately join the first substrate and the second substrate so that the positions of the first substrate and the second substrate do not shift with a simple mechanism. And accuracy can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a perspective view for explaining the configuration of an optical scanner device 1 according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, and FIG. FIG. 4 is a sectional view taken along line B-B in FIG.

  In the following, for convenience of explanation, the upper side of FIGS. 2 and 4 is referred to as “upper”, the lower side is referred to as “lower”, the right side is referred to as “right”, and the left side is referred to as “left”.

The optical scanner device 1 includes a base (first substrate) 2 having a one-degree-of-freedom vibration system as shown in FIG. 1 and a support substrate (second substrate) 3 that supports the base 2. . The optical scanner device 1 is connected to a drive unit 4 for rotating the mass unit 21 and a drive detection unit 5 for detecting the drive state of the mass unit 21.
The base body 2 includes a mass portion 21, a pair of connecting portions 22 and 23, and a pair of support portions 24 and 25. Each of the connecting portions 22 and 23 is formed of an elastic portion having a longitudinal shape and elastically deformable. Therefore, hereinafter, for convenience of explanation, the connecting portion 22 is also referred to as “elastic portion 22”, and the connecting portion 23 is also referred to as “elastic portion 23”.

In such an optical scanner device 1, the mass portion 21 is rotated while twisting and deforming the pair of elastic portions 22 and 23 by applying a voltage to a coil 43 described later. . At this time, the mass portion 21 rotates about the rotation center axis X shown in FIG.
The pair of elastic portions 22 and 23 are provided so as to be substantially symmetrical with respect to the mass portion 21 in a plan view of the mass portion 21 when not driven. That is, the optical scanner device 1 is formed so as to be substantially symmetric with respect to the mass portion 21 in the plan view of the mass portion 21 when not driven.

  The mass portion 21 is a plate-like resin provided so as to be surface-bonded to a plate-like silicon portion 211 made of silicon as a main material and a lower surface of the silicon portion 211 (a surface facing the support substrate 3). Part 212 and a light reflecting part 213 provided on the upper surface of the silicon part 211 (surface opposite to the resin part 212). That is, the mass portion 21 has a stacked structure in which the silicon portion 211, the resin portion 212, and the light reflecting portion 213 are stacked in the thickness direction of the surface of the silicon portion 211. In other words, the mass part 21 is formed such that the silicon part 211 is sandwiched between the resin part 212 and the light reflecting part 213. A coil 43 described later is provided on the lower surface of the resin portion 212 (the surface opposite to the silicon portion 211).

  The support part 24 is a plate-like silicon part 241 made of silicon as a main material, and a plate-like resin part 242 made so as to be surface-bonded to the lower surface of the silicon part 241 and made of a resin material as a main material. It has. That is, the silicon part 241 and the resin part 242 are laminated in the thickness direction. Similarly, the support part 25 is a plate-like silicon part 251 made of silicon as a main material, and a plate made of resin material as a main material provided so as to be surface-bonded to the lower surface of the silicon part 251. The resin part 252 is provided. An amplifier circuit 52 described later is formed on the lower surface of the silicon portion 241 of the support portion 24 among the support portions 24 and 25.

The elastic part 22 connects the mass part 21 and the support part 24 so that the mass part 21 can be rotated with respect to the support part 24. Similarly, the elastic portion 23 connects the mass portion 21 and the support portion 25 so that the mass portion 21 can be rotated with respect to the support portion 25. Such elastic part 22 and elastic part 23 have the same shape and the same dimensions.
The elastic portion 22 and the elastic portion 23 are provided coaxially with each other, and the mass portion 21 is rotatable with respect to the support portions 24 and 25 with the rotation central axis (rotation axis) X as the rotation portion. .
The elastic portion 22 is provided with a stress detection element 51 described later. The elastic part 22 is composed of a silicon part 221 composed of silicon as a main material and a resin part 222 joined to the silicon part 221 and composed of a resin material as a main material.

The base 2 has a laminated structure of a silicon layer and a resin layer.
This silicon layer includes a silicon part 211 of the mass part 21, a silicon part 221 of the elastic part 22, a silicon part 231 of the elastic part 23, a silicon part 241 of the support part 24, and a silicon part 251 of the support part 25. It is formed integrally.
On the other hand, the resin layer includes a resin part 212 of the mass part 21, a resin part 222 of the elastic part 22, a resin part 232 of the elastic part 23, a resin part 242 of the support part 24, and a resin part 252 of the support part 25. Are integrally formed. Such a resin material is not particularly limited as long as the mass portion 21 can be rotated, but various thermoplastic resins and various thermosetting resins can be used. In addition, the recessed parts 61a and 61b provided in the support parts 24 and 25 mentioned later are formed only by the silicon layer.

The substrate 2 is supported on the support substrate 3.
The support substrate 3 has an upper surface (a surface facing the base 2), and a pair of joint portions 32 and 33 are formed at positions facing the support portions 24 and 25, and the joint portions 32 and 33 are formed. The support substrate 3 supports the base 2 by bonding the upper surface of the support member 24 and the lower surfaces of the support portions 24, 25.

Furthermore, an opening 31 is formed in the bottom portion 30 at a portion corresponding to the mass portion 21. The opening 31 constitutes an escape portion that prevents contact with the support substrate 3 when the mass portion 21 rotates (vibrates). By providing the opening 31, the deflection angle (amplitude) of the mass portion 21 can be set larger while preventing the overall size of the optical scanner device 1 from being increased. Note that the opening portion 31 may not be provided in the bottom surface portion 30.
The support substrate 3 is made of, for example, glass or silicon as a main material.

  FIG. 5 is a view showing a bonding surface between the base 2 and the support substrate 3. 5A shows the bottom surface of the base 2 and FIG. 5B shows the top surface of the support substrate 3. FIG. 6 is a view showing a CC cross section of FIG. 6A shows a state before the base 2 and the support substrate 3 are joined, and FIG. 6B shows a joined state. As shown in the figure, recesses 61a and 61b are provided on the bottom surface of the base 2, and a metal film 62 is formed on the surface of the recess 61a.

  On the surface of the support substrate 3, convex portions 63 that fit into the concave portions 61 a and 61 b are formed. The convex portion 63 is formed by arranging a solder alloy in a ball shape. The recesses 61a and 61b of the base 2 can be formed at the same time when the silicon layer of the base 2 is etched. In addition, you may form the convex part 63 with a metal bump or a metal mold other than a solder alloy.

When the base body 2 and the support substrate 3 are joined, the convex portions 63 are fitted into the respective concave portions 61a and 61b, and further, heat is applied and crimped, whereby the metal film 62 and the convex portions 63 of the concave portion 61a are soldered. . Thereby, the recessed part 61a and the convex part 63 are fixed. On the other hand, since the metal film 62 is not provided on the surface of the concave portion 61b, the convex portion 63 is fitted into the concave portion 61b but is not fixed.
In this way, in the direction of the rotation center axis of the mass portion 21, only the concave portion 61a and the convex portion 63 on one side are fixed across the mass portion 21, and the concave portion 61b and the convex portion 63 on the other side are not fixed. Thereby, the stress generated by the influence of heat or the like during driving of the mass unit 21 can be relaxed.

Next, the drive part 4 for rotating the mass part 21 is demonstrated using FIG. FIG. 3 is an enlarged partial cross-sectional view of the lower surface of the base 2 (the surface facing the support substrate 3).
The drive unit 4 is opposed to the coil 43 provided in the resin unit 212 of the mass unit 21, an AC power supply 44 that applies a voltage to the coil 43, and the mass unit 21 in a direction perpendicular to the rotation center axis X. It has a pair of magnets 41 and 42 provided so as to. The drive unit 4 is configured to vibrate (rotate) the mass unit 21 with respect to the support units 24 and 25 by applying an AC voltage from the AC power supply 44 to the coil 43.

  The coil 43 is formed in a spiral shape over almost the entire lower surface of the resin portion 212 of the mass portion 21 (surface opposite to the silicon portion 211). Since the resin part 212 functions as an insulating layer, a short circuit between the wirings of the coil 43 can be prevented. The patterning shape of the coil 43 is not limited to a spiral shape as long as the mass portion 21 can be rotated.

  One of both ends of the electric wire (wiring) forming the coil 43 is connected to a terminal 431 provided on the support portion 24, and the other is connected to a terminal 432 provided on the support portion 25. An AC power supply 44 is connected to the terminals 431 and 432, and the AC power supply 44 can generate a magnetic field from the coil 43 by applying an AC voltage to the coil 43.

The magnet 41 and the magnet 42 are provided to face each other in a direction perpendicular to the rotation center axis X via the mass portion 21 in a plan view of the mass portion 21. Further, the magnets 41 and 42 are provided so that the surface of the magnet 41 facing the magnet 42 and the surface of the magnet 42 facing the magnet 41 are different magnetic poles.
Although it does not specifically limit as magnets 41 and 42, permanent magnets (hard magnetic material), such as a neodymium magnet, a ferrite magnet, a samarium cobalt magnet, and an alnico magnet, can be used conveniently.

The drive unit 4 rotates (drives) the mass unit 21 as follows.
For convenience of explanation, as shown in FIG. 3, as a representative case, the surface of the magnet 41 facing the magnet 42 is an S pole and the surface of the magnet 42 facing the magnet 41 is an N pole. explain. Also, the upper side of FIG. 4 is “upper” and the lower side is “lower”.
First, a case where current is passed through the coil 43 from the terminal 431 to the terminal 432 by the AC power supply 44 (hereinafter referred to as “first state”) will be described. In this case, a downward electromagnetic force in FIG. 4 acts on the portion of the mass portion 21 closer to the magnet 42 than the rotation center axis X (Fleming's left-hand rule). On the other hand, an upward electromagnetic force in FIG. 4 acts on a portion of the mass portion 21 closer to the magnet 41 than the rotation center axis X. Thereby, the mass part 21 rotates counterclockwise around the rotation center axis X.

  On the other hand, when a current is passed through the coil 43 from the terminal 432 to the terminal 431 by the AC power supply 44 (hereinafter referred to as “second state”), the magnet 42 in the mass portion 21 is located more than the rotation center axis X. On the side, an upward electromagnetic force is generated in FIG. On the other hand, a lower electromagnetic force is generated in FIG. 4 on the magnet 41 side of the mass portion 21 with respect to the rotation center axis X. Thereby, the mass part 21 rotates clockwise with the rotation center axis X as an axis.

Then, by alternately repeating the first state and the second state, the mass portion 21 can be rotated with respect to the support portion 24 while the elastic portions 22 and 23 are torsionally deformed.
Furthermore, by using the AC power supply 44 as the voltage application means, the first state and the second state can be switched periodically and smoothly, and the mass portion 21 can be smoothly rotated. . However, the voltage applying means is not limited to the present embodiment (AC power supply 44) as long as a voltage can be applied to the coil 43, and for example, a DC power supply may be used. In this case, for example, the mass portion 21 can be rotated with respect to the support portion 24 by intermittently applying a DC voltage to the coil 43.

Next, the drive detection part 5 which detects the drive state of the mass part 21 is demonstrated.
As shown in FIG. 3, the drive detection unit 5 is formed on the stress detection element 51 provided on the lower surface (surface on the resin unit 222 side) of the silicon unit 221 of the elastic unit 22 and the silicon unit 241 of the support unit 24. And an amplification circuit 52 electrically connected to the stress detection element 51. A plurality of through holes 53 for connecting the stress detection element 51 and the amplifier circuit 52 are formed in the resin portion 242 of the support portion 24. In addition, an input terminal 521 and an output terminal 522 are formed on the resin portion 242 of the support portion 24, and these are electrically connected to the amplifier circuit 52, respectively. As the stress detection element 51, for example, a piezoelectric element (piezo element) can be used.

The drive detection unit 5 is configured to detect the drive state of the mass unit 21 based on a signal from the amplification circuit 52. Specifically, the stress detection element 51 has a property that the resistance value changes in accordance with the amount of deformation. By providing such a stress detection element 51 on the elastic part 22, the resistance value of the stress detection element 51 can be changed corresponding to the degree of torsional deformation (swing angle) of the elastic part 22.
As the resistance value of the stress detection element 51 changes, the current value (electric signal) flowing through the stress detection element 51 changes, and the change in the electric signal is detected by the amplifier circuit 52 formed in the silicon portion 241 of the support portion 24. Amplification is performed, and the driving state of the mass unit 21 is detected based on the amplified signal. Thereby, the drive state of the vibration system of the optical scanner device 1 can be detected more accurately. Based on the detected drive state, the frequency of the voltage applied by the AC power supply 44 is adjusted to control the vibration system of the optical scanner device 1 to vibrate at its own resonance frequency. Thereby, the light reflection part 213 of the optical scanner apparatus 1 can be greatly displaced, and the scanning angle by the optical scanner apparatus 1 can be maximized.

(Image forming device)
The optical scanner device 1 can be suitably applied to an image forming apparatus such as a projector, a laser printer, an imaging display, a barcode reader, a scanning confocal microscope, and the like. As a result, an image forming apparatus having excellent drawing characteristics can be provided.
For example, a projector (image forming apparatus) 90 as shown in FIG. 7 will be described. For convenience of explanation, the longitudinal direction of the screen S is referred to as “lateral direction (horizontal direction)”, and the direction perpendicular to the longitudinal direction is referred to as “vertical direction (vertical direction)”.

The projector 90 includes light source devices 911, 912, 913 that emit light such as a laser, a cross dichroic prism 92, a pair of optical scanner devices 93, 94, and a fixed mirror 95.
The light source devices 911, 912, and 913 are a red light source device 911 that emits red light, a blue light source device 912 that emits blue light, and a green light source device 913 that emits green light.
The cross dichroic prism 92 is configured by bonding four right-angle prisms, and is an optical element that combines light emitted from each of the red light source device 911, the blue light source device 912, and the green light source device 913.

Such a projector 90 synthesizes light emitted from each of the red light source device 911, the blue light source device 912, and the green light source device 913 based on image information from a host computer (not shown) by a cross dichroic prism 92, The combined light is scanned by the optical scanner devices 93 and 94 and further reflected by the fixed mirror 95 to form a color image on the screen S.
Here, the optical scanning of the optical scanner devices 93 and 94 will be specifically described.

First, the light combined by the cross dichroic prism 92 is scanned in the horizontal direction by the optical scanner device 93 (hereinafter also referred to as “main scanning”). The light scanned in the horizontal direction is further scanned in the vertical direction by the optical scanner device 94 (hereinafter also referred to as “sub-scan”). Thereby, a two-dimensional color image can be formed on the screen S.
By using the optical scanner device according to the present invention as such optical scanner devices 93 and 94, it is possible to provide a projector 90 that is small in size and has excellent drawing characteristics.

  In general, the rotation speed of the optical scanner device 94 that performs sub-scanning is lower than the rotation speed of the optical scanner 93 that performs main scanning. Generally, the rotation frequency of the optical scanner device 94 that performs sub-scanning is about 60 kHz, and the rotation frequency of the optical scanner device 93 that performs main scanning is 10 although it depends on the type and size of the image to be formed. It is about ~ 256kHz. From this point of view, by using the optical scanner device of the present invention as the optical scanner devices 93 and 94, an optical scanner device having a torsion spring constant suitable for each of main scanning and sub-scanning can be easily provided. Can do. Therefore, it is possible to provide a projector 90 that is small and exhibits excellent drawing characteristics. However, the configuration of the projector 90 is not particularly limited as long as a color image can be formed on the screen S.

  As described above, according to the first embodiment, the base 2 is formed with a simple mechanism by fitting the concave portions 61 a and 61 b formed on the surface of the base 2 and the convex portions 63 formed on the surface of the support substrate 3. And the support substrate 3 can be accurately bonded so as not to be displaced.

  Further, in the direction of the rotation center axis of the mass portion 21, only the concave portion 61a and the convex portion 63 on one side are fixed across the mass portion 21, and the concave portion 61b and the convex portion 63 on the other side are not fixed. Stress generated by the influence of heat or the like during driving of the mass unit 21 can be relaxed.

  In addition, the structure of each part of the optical scanner device 1 of the present invention can be replaced with an arbitrary structure that exhibits the same function, and an arbitrary structure can be added.

  In the present embodiment, the recesses 61a and 61b are provided in the base 2 and the protrusions 63 that fit into the recesses 61a and 61b are provided in the support substrate 3. However, the recesses are provided on the support substrate 3 side, and the base 2 side is provided. You may make it the structure which provides a convex part. In the present embodiment, the concave portion and the convex portion are fixed by solder bonding, but may be fixed using, for example, an adhesive.

It is a perspective view for demonstrating the structure of the optical scanner apparatus by Embodiment 1 of this invention. It is the sectional view on the AA line of FIG. It is a figure for demonstrating a drive part. It is the BB sectional view taken on the line of FIG. It is a figure which shows the joint surface of a base | substrate and a support substrate. It is CC sectional view taken on the line of FIG. 1 is a schematic diagram for explaining an image forming apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical scanner apparatus, 2 base | substrate, 21 mass part, 211 silicon | silicone part, 212 resin part, 213 light reflection part, 22,23 elastic part (connection part), 221,231 silicon | silicone part, 222,232 resin part, 24,25 Support part, 241, 251 Silicon part, 242, 252 Resin part, 3 Support substrate, 30 Bottom part, 31 Opening part, 32, 33 Joint part, 4 Drive part, 41, 42 Magnet, 43 Coil, 431, 432 Terminal, 44 AC power supply, 5 drive detection unit, 51 stress detection element, 52 amplification circuit, 521 input terminal, 522 output terminal, 53 through hole, 61a, 61b recess, 62 metal film, 63 projection, 90 projector, 911 red light source device , 912 Blue light source device, 913 Green light source device, 92 Cross dichroic prism, 93, 94 Optical scanner 95 fixed mirror

Claims (6)

A mass part provided with a light reflecting part having light reflectivity;
A support part for supporting the mass part;
A connecting portion having an elastic portion that connects the mass portion to the support portion in a rotatable manner; and
An optical scanner device that scans light reflected by the light reflecting portion onto an object by rotating the mass portion while twisting and deforming the elastic portion,
A first substrate comprising the mass part, the support part, and the connecting part;
A second substrate bonded to the first substrate and supporting the first substrate;
An optical scanner device, wherein a concave portion is formed on one of the first substrate and the second substrate, and a convex portion that fits into the concave portion is formed on the other. The support portion of the first substrate is provided with the recess,
The second substrate is provided with the convex portion,
A metal film is formed on the surface of the recess,
The convex portion is formed of a metal material that can be joined to the metal film,
The optical scanner device according to claim 1, wherein the concave portion and the convex portion are metal-bonded.   The optical scanner device according to claim 2, wherein the convex portion is formed of a metal bump.   The optical scanner device according to claim 2, wherein the convex portion is formed of a solder alloy. One of the first substrate and the second substrate has a second recess formed on the opposite side of the recess with the mass portion interposed therebetween, and the other has a rotation center axis direction of the mass portion. A second convex part is formed on the opposite side of the convex part across the mass part,
5. The optical scanner device according to claim 1, wherein the convex portion is fixed to the concave portion, and the second convex portion is fitted into the second concave portion. 6. An image forming apparatus comprising the optical scanner device according to any one of claims 1 to 5,
An image forming apparatus that forms an image on an object by scanning the light reflected by the light reflecting portion by rotating the mass portion.