KR20080096731A - Scanning micromirror - Google Patents

Abstract

A scanning micromirror is provided to improve irradiating speed by micromachining technology and improve optical performance through widening radiation angle. In a scanning micromirror, a substrate(110) is formed on the open area, a ring gimbal(140) is combined with substrate through the first elastic body on the open area, and is operated around axis of the first elastic body. The ring strengthening frame(130) is combined through the second elastic body in the gimbal inside. A mirror plate(120) is combined through the third elastic body in the strengthening frame inside, and is rotated around the azis of has the second elastic body and the third elastic body with the strengthening frame. A coil which is combined on the gimbal and the strengthening frame and mirror plate forms the electromagnetic field and generates the driving force. A magnet forms the electromagnetic field with the coil while being combined with the base face side of substrate.

Description

Scanning micromirror

1 is a perspective view schematically showing a projection display structure using a conventional two-axis scanning micromirror.

Figure 2 is a perspective view schematically showing the structure of a projection display using a conventional one-axis scanning micromirror and galvanometric mirror.

3 schematically illustrates the structure of a scanning display system in which a typical scanning micromirror is implemented in combination with a laser array.

4 is a top perspective view showing the structure of a scanning micromirror according to a first embodiment of the present invention.

Figure 5 is a lower perspective view showing the structure of a scanning micromirror according to a first embodiment of the present invention.

6 is a side cross-sectional view showing the structure of a scanning micromirror according to a first embodiment of the present invention;

7 is a diagram illustrating the basic driving principle of the magnet and the coil provided in the scanning micromirror according to the first embodiment of the present invention.

8 is a diagram illustrating a two-axis driving principle when the coil of the scanning micromirror according to the first embodiment of the present invention is provided with two lines.

9 is a diagram illustrating a two-axis driving principle when the coil of the scanning micromirror according to the first embodiment of the present invention is provided in one line.

10 is a plan view showing a structure in which the coil of the scanning micromirror according to the first embodiment of the present invention is disposed on the plane of the gimbal and the reinforcement frame;

FIG. 11 is a diagram illustrating a simulation result of a resonance mode of a scanning micromirror according to a first embodiment of the present invention by finite element analysis. FIG.

12 is a graph illustrating frequency waveforms of resonance modes of the scanning micromirror according to the first embodiment of the present invention.

FIG. 13 is a top view illustrating a structure in which a coil of a scanning micromirror according to a first embodiment of the present invention is disposed on a gamble, a reinforcement frame, and a mirror plate, and is single-layer wound with three input / output lines.

14 is a top view illustrating a structure in which a coil of a scanning micromirror according to a first embodiment of the present invention is wound on two gimbals, a reinforcement frame, and a mirror plate, and wound in two layers with two input / output lines;

15 is a top perspective view showing a structure of a scanning micromirror according to a second embodiment of the present invention.

16 is a lower perspective view showing the structure of a scanning micromirror according to a second embodiment of the present invention.

17 is a top view illustrating a coupling structure according to a first embodiment in which a mirror plate provided in a scanning micromirror according to a second embodiment of the present invention is coupled to a frame;

18 is a top view illustrating a coupling structure according to a second embodiment in which a mirror plate provided in a scanning micromirror according to a second embodiment of the present invention is coupled to a frame;

19 is a top perspective view showing a structure according to a first embodiment of a magnet provided in the scanning micromirror according to the second embodiment of the present invention.

20 is a top perspective view showing a structure according to a second embodiment of a magnet provided in the scanning micromirror according to the second embodiment of the present invention.

<Explanation of symbols for main parts of drawing>

100: scanning micromirror according to the first embodiment

110: substrate 120: mirror plate

130: Enhanced Frame 140: Gimble

152: first elastic body 154: second elastic body

156: third elastic body 162: first electrode pad

164: second electrode pad 170: a magnet

172: support 174: ring magnet

176: cylindrical magnet 180: first trench

185: second trench 190: coil

195: insulation layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning device, and more particularly, a scanning micromirror that forms an image or reads data by scanning a beam emitted from a light source into a 1D or 2D region. It is about.

Along with the development of optical device technology, various technologies that use light as an input / output terminal and information transfer medium of various information are emerging, such as a barcode scanner or a basic scanning laser display. A typical example is a technique of scanning and using a beam emitted from a light source. In particular, recently, a system using high spatial resolution beam scanning has been developed, and such a system includes a projection display system having excellent high-resolution primary color reproduction using laser scanning. Or a head mounted display (HMD) or a laser printer.

This beam scanning technique requires a scanning mirror having various scanning speeds and scanning ranges (angular displacements, tilting angles), depending on the application. Conventional beam scanning requires a galvanic mirror. And the angle of incidence between the incident light and the reflective surface of the driven mirror, such as a rotating polygon mirror).

Scanning speeds of several to tens of hertz (Hz) can be realized when using galvanic mirrors, and scanning speeds of several kilohertz (kHz) can be realized when using polygonal mirrors. That is, in the case of the polygon mirror, since the polygon mirror is mounted on the motor that rotates at a high speed, the scanning speed is proportional to the rotational angular velocity of the polygon mirror, which is dependent on the rotational speed of the driving unit motor, thus limiting the conventional motor rotational speed. Due to the limitation in increasing the scanning speed, there is a disadvantage that it is difficult to reduce the volume and power consumption of the entire system. In addition, the mechanical friction noise of the drive motor unit must be fundamentally solved, and it is difficult to expect cost reduction due to the complicated structure.

On the other hand, in the case of a scanning device using a micromirror, bidirectional scanning is possible, and a high scanning speed of several tens of kHz can be realized.

1 is a perspective view schematically showing a projection display structure using a general two-axis scanning micromirror.

As shown in FIG. 1, the biaxial scanning micromirror can be biaxially driven through the gamble 2 and the mirror plate 1, and independent driving signals are input to the gamble 2 and the mirror plate 1, respectively. The shape in which the input light L1 is reflected and scanned into the two-dimensional image L2 is shown.

As such, in order to implement two-axis scanning using a micromirror, a method of using a two-axis scanning micromirror with a gimbal structure, a method of using a separate one-axis scanning mirror for two driving axes, a scanning micromirror and a galvanometric Or a mirror or laser array.

2 is a perspective view schematically showing the structure of a projection display using a general uniaxial scanning micromirror and a galvanometric mirror, and FIG. 3 is a schematic view of a structure of a scanning display system in which a general scanning micromirror is implemented in combination with a laser array. It is a figure shown.

According to FIG. 2, the light incident from the light source 1 is reflected by the micromirror 3 via the optical system 2 composed of several lenses. At this time, the magnet 4 is provided on the side of the micromirror 3 to form an electromagnetic field, and the micromirror is driven in the horizontal direction to convert incident light into line segments on the x-axis. The converted light is composed of components on the y-axis by the galvanometric mirror driven in the vertical direction, thereby producing a two-dimensional image L3 as a whole.

In addition, according to FIG. 3, the light source, that is, the laser array 6 configures and scans the light of the horizontal component and the light on the x-axis, and the lens 7 evenly arranges the light and transmits it to the micromirror 8. The micromirror 8 is vertically driven to form a two-dimensional image L4 by reflecting light.

In this case, a two-axis scan for display requires a high scan rate of several tens of kHz in the horizontal direction, while a relatively low speed of several tens of Hz is required in the vertical direction. Resonant driving method is used to secure the angle, and forced driving method is used in the vertical direction.

However, in the case of the conventional constant power drive scanning micromirror using the comb electrode in the vertical direction, the high alignment accuracy of the movable part or the rotor and the fixed part or stator in the manufacturing process In order to increase the rotation angle, there is a difficulty in manufacturing a structure having a high aspect ratio. In addition, both the movable comb-shaped electrode attached to the mirror plate and the fixed comb-shaped electrode adjacent thereto have a disadvantage of acting as a factor of increasing damping during driving.

The present invention is manufactured through a micromachining process or a micromachining process, and can be applied to both uniaxial or biaxial driving methods, and can realize a faster scanning speed and a wider driving angle (scanning range). Structural stability to high speed operation is secured, and optical performance is prevented from being degraded according to conventional physical operations, so that scanning is applicable to various beam scanning systems such as a high performance scanning system requiring high spatial resolution and a system requiring static displacement. It is an object to provide a micromirror.

In order to achieve the above object, the scanning micromirror according to the present invention comprises a substrate having an open area; A ring-shaped gamble coupled to the substrate on the open region through a first elastic body and driven using the first elastic body as a rotation axis; A ring-shaped reinforcing frame coupled inside the gimbal through a second elastic body; A mirror plate coupled to the inside of the reinforcement frame through a third elastic body and driven together with the reinforcement frame using the second elastic body and the third elastic body as rotation axes; A coil coupled to the gamble, the reinforcement frame and the mirror plate to form an electromagnetic field to generate a driving force; And a magnet coupled to the bottom surface side of the substrate and forming an electromagnetic field together with the coil.

In order to achieve the above object, the scanning micromirror according to the present invention comprises a substrate having an open area; A mirror plate coupled to the substrate on the open area through an elastic body, the mirror plate having a rectangular reflective area, and driven with the elastic body as a rotation axis; A coil coupled to the mirror plate to form an electromagnetic field to generate a driving force; And a magnet coupled to the bottom surface side of the substrate and forming an electromagnetic field together with the coil.

In addition, the second elastic body and the third elastic body of the scanning micromirror according to the present invention are located on a straight line to provide a rotation axis of the reinforcement frame and the mirror plate, wherein the first elastic body is the second elastic body and the first elastic body. It is characterized in that it is positioned perpendicular to the axis of rotation of the three elastic bodies to provide the axis of rotation of the gamble.

In addition, the elastic body of the scanning micromirror according to the present invention comprises one or more torsion bars, the torsion bar is characterized in that the combination of one or more forms of straight or curved.

In addition, the magnet of the scanning micromirror according to the present invention is a ring-shaped magnet; Cylindrical magnets spaced apart from inside the ring magnet; And it characterized in that it comprises a support for coupling the ring-shaped magnet and the cylindrical magnet on the bottom side.

In addition, the magnet of the scanning micromirror according to the present invention comprises at least two rectangular magnets arranged side by side with a distance from each other; And a support for coupling the magnets to each other.

In addition, the gamble, the reinforcement frame and the mirror plate of the scanning micromirror according to the present invention are forcibly driven based on the rotation axis of the first elastic body when a low frequency first frequency signal is applied to the coil. When the high frequency second frequency signal is applied to the coil is characterized in that the resonant drive with respect to the rotation axis of the second elastic body and the third elastic body.

In addition, the elastic body of the scanning micromirror according to the present invention is composed of two parts that are opposed to each other, the coil is a single wire and single layer structure, and constitutes a gamble path from one side of the first elastic body to one side of the second elastic body, A first coil part constituting a semicircular path of the reinforcing frame and penetrating the mirror plate from the second elastic body to the second elastic body, and constituting a gamble path from the second elastic body to the other first elastic body; And forming a gamble path from the first elastic body to the second elastic body, penetrating the mirror plate from the second elastic body to the second elastic body, and configuring the other semicircular path of the reinforcement frame after the other side agent. And a second coil part constituting the gimbal path from the second elastic body to the other first elastic body.

In addition, the elastic body of the scanning micromirror according to the present invention is composed of two parts facing each other, the coil is a double wire and a multi-layer structure, branched from the input line of one side of the first elastic body to form a circular path on the gamble And a first coil part forming an output line from the other first elastic material; And insulated from the first coil part, enters the reinforcing frame from the first elastic body on one side through the second elastic body, forms a circular path on the reinforcing frame, and passes the second elastic body to the other first elastic body. And a second coil part forming an output line.

In addition, the elastic body of the scanning micromirror according to the present invention is composed of two parts that are opposed to each other, the coil is a double wire and single layer structure, each of the semi-circular path on the gamble from the first elastic body to the other first elastic body A first coil part and a second coil part to constitute; And a second coil part which enters the reinforcing mold from the first elastic body on one side through the second elastic body, forms a circular path on the reinforcing frame, and forms an output line to the other first elastic body through the second second elastic body. Characterized in that comprises a.

Hereinafter, a scanning micromirror according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

4 is a top perspective view showing the structure of the scanning micromirror 100 according to the first embodiment of the present invention, and FIG. 5 is a view showing the structure of the scanning micromirror 100 according to the first embodiment of the present invention. FIG. 6 is a side sectional view showing the structure of the scanning micromirror 100 according to the first embodiment of the present invention.

4 to 6, the scanning micromirror 100 according to the first embodiment of the present invention includes a substrate 110, a mirror plate 120, a gimbal 140, Reinforcement rim 130, first elastic body 152, second elastic body 154, third elastic body 156, insulator 195, coil 190, first electrode pad 162, first It comprises a two electrode pad 164 and a magnet 170, first, each component will be described as follows.

The mirror plate 120 is connected to the reinforcement frame 130 through the first elastic body 152, and the gamble 140 is connected to the reinforcement frame 130 through the second elastic body 154.

The mirror plate 120 may be formed of a laminated structure including a metal and a dielectric. The mirror plate 120 may have a flat structure with a uniform thickness or a convex center portion thicker than an outer portion.

In addition, the gamble 140 is connected to the substrate 110 through the third elastic body 156, so that the mirror plate 120, the reinforcement frame 130 and the gamble 140 are supported on the substrate 110 and the The first elastic body 152, the second elastic body 154 and the third elastic body 156 may be respectively flow at a predetermined rotation angle.

The second elastic member 154 is a component that serves as a kind of spring role (torsion bar), and serves as a rotating shaft at both ends of the mirror plate 120, the restoring force torque when the mirror plate 120 is driven Provides Torque.

The third elastic body 156 also serves as a kind of spring, and serves as a rotating shaft at both ends of the gamble 140, and provides a restoring force torque when the gamble 140 is driven.

The rotation axis formed by the second elastic body 154 and the third elastic body 156 is perpendicular to each other so that the mirror plate 120 may be vertically flowed in two axes, and the mirror plate 120 and the gimbal 140 May be manufactured in any form, but since it flows in two axes, it is preferable that the reflection area for each axis is circular or elliptical.

The elastic bodies 152, 154, and 156 may have a form such as cantilever, torsion beam, meander beam, or the like.

4 and 6, when viewing the upper surface of the scanning micromirror 100 according to the first embodiment of the present invention, the third elastic body 156, the gimbal 140, the second elastic body 154, It can be seen that the coil 190 is formed on the surface of the reinforcement frame 130, the first elastic body 152, and the mirror plate 120, and the coil 190 is coupled between the surface of each component and the coil 190. An insulating layer 195 is formed and electrically isolated.

In addition, two electrode pads 162 and 164 are provided on an upper surface of the substrate to provide a current to the coil, and two third elastic bodies 156 connected to both ends of the gimbal 140 have their respective ends. It is connected to the first electrode pad 162 and the second electrode pad 164.

The coil 190 is at least one conductor layer, and the current flowing into the third elastic body 156 and the gimbal 140 through the first electrode pad 162 is formed on the second elastic body 154 and the reinforcement frame 130. After flowing to the coil 190 and penetrating through the center of the mirror plate 120, it flows again to the second electrode pad 164 through the third elastic body 156 and the gimbal 140.

The material of the coil 190 may be a metal such as Ti, Cr, Cu, Ag, Ni, Al, or a single material such as indium tin oxide (ITO), a conductive polymer, or a combination thereof.

The detailed structure and current flow of the coil 190 will be described later in detail with reference to FIGS. 9 to 11.

When the electric field is formed through the current flow on the coil 190, it interacts with the magnetic field of the magnet 170 positioned below the substrate to form a physical force, that is, the Lorentz force, and the Lorentz force is the coil ( When acting on 190, the gamble 140 and the mirror plate 120 flow about two axes.

The reinforcement frame 130 is a component for preventing the mirror plate 120 from being thermally deformed (for example, the mirror plate may be distorted due to external heat) or fluttering during the flow (dynamic deformation). The mirror plate 120 flows in the same direction and at the same rotation angle.

5 and 6, the bottom surface of the substrate 110 may be etched to form a first trench 180 and a second trench 185. The first trench 180 may be formed as described above. The second trench 185 is etched to reduce the thickness of the third elastic body 156 while providing a space in which the gamble 140, the reinforcement frame 130, and the mirror plate 120 can move. The third elastic body 156 is formed longer and thinner than other elastic bodies to reduce the spring constant).

7 is a diagram illustrating the basic driving principle of the magnet 170 and the coil 190 provided in the scanning micromirror 100 according to the first embodiment of the present invention, and FIG. 8 is a first embodiment of the present invention. FIG. 9 is a diagram illustrating a two-axis driving principle when the coil 190 of the scanning micromirror 100 is provided with two lines, and FIG. 9 is a coil of the scanning micromirror 100 according to the first embodiment of the present invention. If 190 is provided with one line, it is a diagram illustrating a two-axis driving principle.

As described above, in order for the gamble 140 and the mirror plate 120 to flow about two axes by the force of Lorentz, the shape and arrangement of the magnet 170 are important. The magnet 170 according to the present invention has a planar shape. It forms a radial magnetic field from the center to the outside. Through this magnetic field shape, the two-axis drive can be best implemented.

First, referring to FIG. 7, the magnet 170 includes a cylindrical magnet 176, a ring magnet 174, and a support 172, and the cylindrical magnet 176 is positioned inside the ring magnet 174. do.

The ring magnet 174 and the cylindrical magnet 176 has a space concentrically spaced, which is to ensure the space in which the electromagnetic field is formed, the ring magnet 174 and the cylindrical magnet 176 is the same thickness as the support 172 is coupled to the top surface.

In order to maximize the radial magnetic field, the ring magnet 174 and the cylindrical magnet 176 are magnetized in opposite directions, and the support 172 may be made of a material such as pure iron having a high relative permeability. .

Referring to FIG. 7, on the substrate 110 (that is, the mirror plate 120, the first elastic body 152, the second elastic body 154, the third elastic body 156, the reinforcement frame 130, and the gimbal 140) The shape of the coil 190 is formed on the magnet 170, the coil 190 is arranged in a concentric circle with respect to the center of the cylindrical magnet 176.

First, when the current 2I flows through the first electrode pad 162, the current 2I branches from the circular coil and proceeds simultaneously in both directions, and the current I on both sides simultaneously progresses to the second electrode pad 164. It flows to the side.

As such, when the same amount of current I in the line symmetry flows on the coils, they are subjected to the force F in the vertical direction by the magnetic field H _r , and thus the torque represented by the following equation (1). (T) is acted on.

Here, "r ₁ " means the radius of the circular coil,

"μ" means permeability of air,

"H _r " means Radial Magnetic Field Intensity.

Therefore, independent torques (T _vertical and T _horizontal ) are provided with respect to two rotation shafts orthogonal to each other (the rotation shaft formed by the first elastic body 152 and the second elastic body 154 and the rotation shaft formed by the third elastic body 156). To do this, two coils 190 are electrically separated as shown in FIG. 8.

According to Figure 8, the large diameter circular coil 190 at the bottom is a portion coupled to the gimbal 140, the large diameter circular coil 190 at the top is a portion coupled to the reinforcement frame 130, the lower coil The current I _v flowing in and the current I _h flowing upward are used independently for driving the vertical axis and the horizontal axis.

However, instead of using an electrically separated coil 190 as shown in FIG. 8, it is possible to allow torque to be applied in two axial directions by changing the winding structure using one coil 190 line as shown in FIG. 9. Can be.

At this time, since the current flows in the opposite direction to the portion where the upper coil and the lower coil are connected, no force is applied, and in the two parallel windings passing through the center of the upper coil, a horizontal force rather than a torque is theoretically applied. Done.

Thus, when the coil (two upper circular coil and the lower circular coil of FIG. 9) arranged in the gimbal 140 and the reinforcement frame 130 through one coil line is configured, unlike one of the input and output terminals of FIG. This exists and the same current (I _v ) flows in the two parts, it is impossible to independently control the torque applied in the vertical and horizontal directions.

However, if the drive frequency is distributed by varying the design of the structure supporting the winding, that is, the gimbal 140, the reinforcement frame 130, the mirror plate 120, and the elastic bodies 152, 154 and 156, the independent two-axis driving is performed. In this case, the structure of the scanning micromirror 100 may be simplified and the manufacturing cost may be reduced by reducing the manufacturing process.

Accordingly, in the first embodiment of the present invention, the winding structure shown in FIG. 9 is used, and the coil structure shown in FIG. 9 is three-dimensionally illustrated to explain the principle, and is actually disposed on a plane.

10 is a plan view showing a structure in which the coil 190 of the scanning micromirror 100 according to the first embodiment of the present invention is disposed on the plane of the gamble 140 and the reinforcement frame 130.

Referring to FIG. 10, the coil 190 is formed of one patterned metal layer, and the path of current is explained as follows.

The current input through the first electrode pattern 162 flows through the third elastic body 156 on one side and branches to both sides when it reaches the circular coil on the gamble 140. The current branched to both sides enters the circular coil on the reinforcement frame 130 through the second elastic bodies 154 on both sides, and the coil 190 on the reinforcement frame 130 and the mirror plate 120 is formed of the semicircular coil. The two parts are arranged opposite each other.

The current entered through the second elastic body 154 on one side flows along the semicircular coil on one side and along the line of the mirror plate 120, and then again along another line on the second elastic body 154 on the one side. It comes out as a line on the gamble 140.

The current entered through the second elastic body 154 on the other side flows along another line of the mirror plate 120 and flows along the semicircular coil 190 on the other side, and then again another line on the second elastic body 154 on the other side. As it flows along it emerges on the opposite coil line on the gamble 140.

Here, the current flowing in the coil on the gimbal 140, the reinforcement frame 130 and the mirror plate 120 flows in the same direction with the upper part and the lower part with the second elastic body 154 as an axis, that is, based on the axis. Flow parallel to line symmetry.

The coil structure implemented as a single line through such a structure has the same radial magnetic field as the structure of the coil 190 implemented as a separate line along the side of the gimbal 140, the reinforcement frame 130, and the mirror plate 120. Can be formed.

FIG. 11 is a diagram illustrating a simulation result of a resonance mode of the scanning micromirror 100 according to the first embodiment of the present invention by finite element analysis.

FIG. 11A illustrates a first resonance mode, (b) illustrates a fifth resonance mode, and FIG. 11C illustrates a sixth resonance mode.

In the biaxial drive according to the first embodiment of the present invention, the internal structure including the gimbal 140 drives the third elastic body 156 to rotate about the axis, and the reinforcement frame 130 and the mirror plate 120 are first The first elastic body 152 and the second elastic body 154 are implemented by a combination of driving the axis, the resonance mode is classified according to these combinations.

Among them, the driving modes of the scanning micromirror 100 required in connection with the two-axis driving are the first resonance mode, the fifth resonance mode, and the sixth resonance mode, as shown in FIG. The illustrated first resonance mode is a mode in which internal structures including the gamble 140 rotate the third elastic body 156 about an axis, also referred to as "force mode."

In addition, (b) the fifth resonance mode illustrated in the drawing is a mode in which the gimbal 140, the mirror plate 120, and the reinforcement frame 130 rotate in the same direction about the second elastic body 154, and (c) In the sixth resonance mode shown in the drawing, the gimbal 140, the mirror plate 120, and the reinforcement frame 130 rotate the second elastic body 154 about the axis, but the mirror plate 120 and the reinforcement frame 130 The mode in which the rotation direction is opposite to the gamble 140 is generally abbreviated as "resonant mode".

Such resonance modes can be shifted according to the shape, density, modulus of elasticity, and spring constant of the structure, and the transition order and resonance frequency of each resonance mode can be changed.

The sixth resonant mode shown in FIG. 12C is used to realize two-axis driving with a coil arrangement structure of one line like the scanning micromirror 100 according to the first embodiment of the present invention. It is possible by simultaneously flowing a drive current having two or more frequencies corresponding to different resonance modes to the coil 190.

12 is a graph illustrating frequency waveforms of resonance modes of the scanning micromirror 100 according to the first exemplary embodiment of the present invention.

FIG. 13A is a waveform of a current inputted in the first resonant mode (hereinafter referred to as "f1"), and (b) a diagram of a current inputted in the sixth resonant mode (hereinafter referred to as "f6"). Waveform, and (c) the measurement of the frequency waveform of the current of the current of f1 and the current of f6 combined.

When the frequency of the current input in the fifth resonance mode is referred to as “f5”, when the current of f1 and the current of f6 (or f5) are simultaneously applied to the coil 190, the current of f ₁ may be applied to the coil on the gimbal 140 ( 190 acts effectively in the path to drive the first resonant mode, and the current of f6 (or f5) acts effectively in the coil mirror 190 on the reinforcement frame 130 to form the sixth resonant mode (or 5 resonant mode).

The first resonant mode is a drive for scanning in the vertical direction of the screen and is forcibly driven at a frequency speed of several tens of Hz (scanned light is scanned) (for example, 60 Hz for a 60-frame image), and the sixth resonant mode. Is a resonant drive at a frequency rate of several tens of kHz as a scan for the horizontal direction of the screen (e.g., in the case of 60 frames of image, the frequency frequency in the vertical direction is the frequency speed in the horizontal direction x 60 ÷ 2). With a frequency speed of about 19 kHz).

When a current of a frequency band significantly lower than f1 is applied, a resonance mode corresponding to a frequency band significantly lower than f1 is forcibly driven instead of the first resonance mode, and the driving direction thereof is the same as that of the first resonance mode.

As such, the frequency of the applied current is selected to properly form the resonance modes for the two drive shafts, and the shape of a structure such as a magnet must also be designed according to the electromagnetic phenomenon, and the gamble 140 and the elastic bodies 152, 154, and 156 may be used. In addition, the arrangement of the coil 190 should be efficiently designed so that the driving force is well transmitted to each component such as the reinforcement frame 130 and the mirror plate 120.

As described with reference to FIG. 10, the arrangement of the coil 190 for two-axis driving may apply various arrangement methods in addition to the method of using one winding connected in series.

FIG. 13 illustrates three input / output lines in the coil 190 of the scanning micromirror 100 according to the first embodiment of the present invention disposed on the gamble 140, the reinforcement frame 130, and the mirror plate 120. 14 is a top view illustrating a structure in which a single layer is wound, and FIG. 14 illustrates a coil 190 of a scanning micromirror 100 according to a first embodiment of the present invention, a gamble 140, a reinforcement frame 130, and a mirror plate ( 120 is a top view illustrating a structure in which two layers of two input / output lines are wound.

Referring to FIG. 13, a total of three coils 190 lines are arranged, and a coil part for driving the gamble 140 and a coil part for driving the mirror plate 120 and the reinforcement frame 130 are separated and gambled. 140, the coil part for driving can be seen again divided into two parts.

That is, the first coil line 190a enters the third elastic body 156 on one side, forms a left semicircle path of the gamble 140, and then goes out to the third elastic body 156 on the other side, and the third coil line 190c It enters the third elastic body 156 on one side and constitutes the right semicircular path of the gamble 140, and then goes out to the third elastic body 156 on the other side.

The second coil line 190b constitutes a path of the gamble 140 from the third elastic body 156 on one side to the second elastic body 154 on the one side, and the reinforcement frame 130 through the second elastic body 154 on the one side. ) And a circular line, connected to the gamble 140 side through the second elastic body 154 on the other side, and constitutes a path of the gamble 140 to the third elastic body 156 on the other side.

Referring to FIG. 14, a total of two coil lines 190a and 190b are disposed, the coil portion 190a for driving the gamble and the coil portion 190b for driving the mirror plate 120 and the reinforcement frame 130. This is separated.

The arrangement structure illustrated in FIG. 14 is different from the arrangement structure described with reference to FIG. 13. The first coil 190a and the third coil 190c are formed as a single line without being separated, and share input / output lines. In order to share the input / output line (that is, form a circular line), the second coil 190b connected to the reinforcement frame 130 is insulated from and connected to the upper (or lower) layer.

Thus, it can be seen that two metal layers are used which are substantially insulated.

Next, the scanning micromirror 200 according to the second embodiment of the present invention will be described. The scanning micromirror 200 according to the second embodiment of the present invention is a single-axis drive type.

15 is a top perspective view illustrating a structure of a scanning micromirror according to a second embodiment of the present invention, and FIG. 16 is a bottom perspective view illustrating a structure of a scanning micromirror according to a second embodiment of the present invention.

15 and 16, the scanning micromirror 200 according to the second embodiment of the present invention includes a mirror plate 210, a frame 220, a coil 230, an elastic body 240, a substrate 250, The first electrode pad 262 and the second electrode pad 264 are included.

The mirror plate 210 is fixed to the frame 220, and both ends of the frame 220 are coupled to the substrate 250 by an elastic body 240.

The elastic body 240 is located opposite to each other on both sides of the frame 220, is provided with a "V" shaped spring, and is elastically supported by the elastic body 240 (since it provides a resilience torque), the elastic body ( It may flow at a predetermined rotation angle with the longitudinal direction of the 210 as an axis.

Since the scanning micromirror 200 according to the second embodiment of the present invention is uniaxially driven, the mirror plate 210 preferably has a rectangular shape, and the frame 220 supporting the mirror plate 210 has an elliptical shape.

The coil 230 is disposed on the upper surface of the frame 220 and the elastic body 240, and the coils 230 of each of the elastic bodies 240 at both ends of the frame 240 may have a first electrode pad 262 and a second electrode. The current flows in connection with the pad 264.

The elastic body 240 and the frame 220 are electrically insulated from the coil 230. The coil 230 is a single conductor layer, which flows through the first electrode pad 262 and the one side elastic body 240. The branched current is branched to both sides of the frame 240 and the branched current reaches the other elastic body 240 and merges.

As such, when current flows along the coil 230 and an electric field is formed, it interacts with the magnetic fields of the magnets 270a and 270b (shown in FIGS. 19 and 20) positioned below the substrate 250 to form a physical force, When the force is formed and the Lorentz force is applied to the coil 230, the frame 220 and the mirror plate 210 coupled to the coil 230 are driven.

Referring to FIG. 16, the bottom surface of the substrate 250 may be etched to form a first trench 266 and a second trench 268. The first trench 266 may be a mirror plate 210. In order to provide a space in which the frame 220 can move, the second trench 268 is an etched space to adjust the thickness of the elastic body 240.

FIG. 17 is a top view illustrating a coupling structure according to the first embodiment in which a mirror plate 210a provided in the scanning micromirror 200 according to the second embodiment of the present invention is coupled to the frame 220a. 18 is a top view illustrating a coupling structure according to the second embodiment in which the mirror plate 210b provided in the scanning micromirror 200 according to the second embodiment of the present invention is coupled to the frame 220b.

According to FIG. 17, the mirror plate 210a and the frame 220a are integrally coupled as an ellipse, the elastic body 240a is implemented in the form of a torsion bar, and the coil 230a is the frame 220a and the elastic body 240a. ) Is coupled on. In addition, according to FIG. 18, the mirror plate 210b is connected to the frame 220b with a space therebetween, and the frame 220b and the mirror plate 210b are coupled through the connecting teeth 214b.

In the coupling structure according to the second embodiment, the frame 220b serves as a reinforcing frame to prevent the mirror plate 210b from being thermally deformed or dynamically deformed.

Since the scanning micromirror 200 according to the second embodiment of the present invention is driven by the same principle as the first embodiment, the repeated description thereof will be omitted.

19 is a top perspective view showing a structure according to the first embodiment of the magnet 270a provided in the scanning micromirror 200 according to the second embodiment of the present invention, and FIG. 20 is a second embodiment of the present invention. The upper perspective view showing the structure according to the second embodiment of the magnet 270b provided in the scanning micromirror 200 according to the present invention.

As described above, in order for the mirror plate 210 to be driven by the force of Lorentz, the shape and arrangement of the magnet 270 is important. The magnet 270 according to the present invention has a radial magnetic field directed from the center on the plane to the outside. Radial Magnetic Field) is formed.

According to FIG. 19, the magnet 270a according to the first embodiment includes a cylindrical magnet 276a, a ring magnet 274a, and a support 272a, which according to the first embodiment of the present invention described above. The structure of the magnet 170 provided in the scanning micromirror 100 is the same.

According to FIG. 20, the magnet 270b according to the second embodiment includes three rectangular magnets 274b, 276b, and 278b and a support 272b, and the three magnets 274b, 276b, and 278b Spaced apart from each other and arranged side by side and coupled to the support (272b).

Since the mirror plate 220 and the coil 230 have the shape of an elliptical ellipse, such a structure may be more advantageous for generating a driving force by the Lorentz force.

That is, the magnet according to the first embodiment shown in FIG. 19 has a strong radioactivity, whereas the magnet according to the second embodiment shown in FIG. 20 has a weak magnetic field radiated to a long side, and a short side (lateral direction). ), The magnetic field is strongly formed, which strongly interacts with the elliptical coil, resulting in stronger uniaxial driving force.

Although the present invention has been described above with reference to the embodiments, these are only examples and are not intended to limit the present invention, and those skilled in the art to which the present invention pertains may have an abnormality within the scope not departing from the essential characteristics of the present invention. It will be appreciated that various modifications and applications are not illustrated. For example, each component specifically shown in the embodiment of the present invention can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

According to the scanning micromirror according to the present invention, the following effects are obtained.

First, a lighter and smaller scanning micromirror can be implemented by applying semiconductor integrated process and micromachining technology, and thus, an optical scanning device in which the micromirror is integrated can be manufactured.

Second, the optical speed is improved by increasing the irradiation speed and the range of the irradiation angle is wider, and there is an effect that can prevent physical deformation due to the high speed operation through the structural improvement, and modulates the path of the reflected light by a predetermined amount Modulation or each modulation function can be provided.

Third, the micromirror can be manufactured through micromachining technology and semiconductor process without conventional substrate bonding or high precision alignment process, which simplifies the process, reduces the production cost, and can drive the optical scanning device with less voltage. It works.

Claims (10)

A substrate on which an open area is formed; A ring-shaped gamble coupled to the substrate on the open region through a first elastic body and driven using the first elastic body as a rotation axis; A ring-shaped reinforcing frame coupled inside the gimbal through a second elastic body; A mirror plate coupled to the inside of the reinforcement frame through a third elastic body and driven together with the reinforcement frame using the second elastic body and the third elastic body as rotation axes; A coil coupled to the gamble, the reinforcement frame and the mirror plate to form an electromagnetic field to generate a driving force; And And a magnet coupled to the bottom surface side of the substrate and forming an electromagnetic field together with the coil. A substrate on which an open area is formed; A mirror plate coupled to the substrate on the open area through an elastic body, the mirror plate having a rectangular reflective area, and driven with the elastic body as a rotation axis; A coil coupled to the mirror plate to form an electromagnetic field to generate a driving force; And Scanning micromirror comprising a magnet coupled to the bottom side of the substrate, the magnet to form an electromagnetic field with the coil. The method of claim 1, The second elastic body and the third elastic body are positioned on a straight line to provide a rotation axis of the reinforcement frame and the mirror plate, The first elastic body is a scanning micromirror, characterized in that it is positioned perpendicular to the rotation axis of the second elastic body and the third elastic body to provide a rotation axis of the gamble. The method of claim 1, wherein the elastic body is It consists of one or more torsion bars, The torsion bar is scanning micromirror, characterized in that the combination of one or more of the straight or curved form. The method of claim 1 or 2, wherein the magnet is Ring magnets; Cylindrical magnets spaced apart from inside the ring magnet; And Scanning micromirror comprising a support for coupling the ring-shaped magnet and the cylindrical magnet on the bottom side. The method of claim 2, wherein the magnet Two or more rectangular magnets disposed side by side at a distance from each other; And And a support for coupling the magnets to each other. The method of claim 1, When the low frequency first frequency signal is applied to the coil, the gamble, the reinforcement frame, and the mirror plate are forcibly driven based on the rotation axis of the first elastic body. And a high frequency second frequency signal is applied to the coil, and the reinforcement frame and the mirror plate are resonantly driven with respect to the rotation axes of the second elastic body and the third elastic body. The method of claim 1, The elastic body is composed of two parts that are located opposite each other, The coil has a single wire structure and a single layer structure, and constitutes a gamble path from one side of the first elastic body to one side of the second elastic body, forms a semicircular path of one side of the reinforcing frame, and then forms the mirror plate from the other side of the second elastic body to the one side of the second elastic body. A first coil part penetrating and constituting a gamble path from the second elastic body on one side to the first elastic body on the other side; And forming a gamble path from the first elastic body to the second elastic body, penetrating the mirror plate from the second elastic body to the second elastic body, and configuring the other semicircular path of the reinforcement frame after the other side agent. And a second coil part constituting the gamble path from the second elastic body to the other first elastic body. The method of claim 1, The elastic body is composed of two parts that are located opposite each other, The coil has a double wire and a multilayer structure, the first coil part branching from an input line of one side of the first elastic body to form a circular path on the gamble and forming an output line of the other side of the first elastic body; And insulated from the first coil part, enters the reinforcing frame from the first elastic body on one side through the second elastic body, forms a circular path on the reinforcing frame, and passes the second elastic body to the other first elastic body. And a second coil portion forming an output line. The method of claim 1, The elastic body is composed of two parts that are located opposite each other, The coil has a double wire and a single layer structure, each of the first coil part and the second coil part constituting a semicircular path on the gimbal from the first elastic body to the other first elastic body; And a second coil part which enters the reinforcing mold from the first elastic body on one side through the second elastic body, forms a circular path on the reinforcing frame, and forms an output line to the other first elastic body through the second second elastic body. Scanning micromirror comprising a.

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