KR20160035310A - Scanning micromirror - Google Patents

Abstract

A scanning micromirror according to an embodiment is disclosed. More specifically, a scanning micromirror capable of two-degree-of-freedom driving is disclosed. The scanning micromirror according to an embodiment comprises a first gimbal driven using a first driving shaft as a rotation shaft, a second gimbal coupled to the inside of the first gimbal through a second driving shaft and driven using the second driving shaft as a rotation shaft, a reflective surface coupled to the inside of the second gimbal through a support, a first coil generating a driving force for driving the first gimbal, and a second coil generating a driving force for driving the second gimbal.

Description

[0002] SCANNING MICROMIRROR [0003]

A scanning micromirror according to one embodiment is disclosed, and more specifically, a scanning micromirror capable of two-degree-of-freedom driving is disclosed.

In addition to the development of optical device technology, technologies using light as a medium for input / output of various information and information transmission include scanning a beam coming from a light source such as a barcode scanner or a basic level display (scanning laser display) There are things that you use. Systems using high spatial resolution beam scanning have been developed and are being developed using a projection display system or HMD (Head Mounted Display), which has high resolution primary color reproduction using laser scanning, Laser printers, and the like.

Such a beam scanning technique requires scanning mirrors having various scanning speeds and scanning angles (angular displacement, angular displacement, tilting angle) according to application examples. In the conventional beam scanning, a galvanic mirror ) Or a rotating polygon mirror and the angle of incidence between the reflecting surface of the mirror and the incident light.

For example, Japanese Patent Application Laid-Open No. 2006-0016638 discloses an optical scanning device that modulates the direction of reflected light by activating a micromirror that reflects input light in a predetermined direction.

An object of the present invention is to provide a scanning micromirror using an electromagnetic force driving method using a radial magnetic field.

An object of the present invention is to provide a scanning micromirror capable of driving two degrees of freedom regardless of a driving frequency.

An object of the present invention is to provide a scanning micromirror capable of driving two degrees of freedom without resonance driving.

An object of the present invention is achieved by providing a scanning micromirror as described below.

The scanning micromirror according to an exemplary embodiment includes a first gimble driven with a first driving shaft as a rotation axis, a second gimble coupled with the inside of the first gimble through a second driving shaft, driven with the second driving shaft as a rotation axis, A first coil for generating a driving force for driving the first gimbals, and a second coil for generating a driving force for driving the second gimbals.

Wherein the first coil is branched from a first drive shaft at a point where the first drive shaft meets the first gimbals and forms a semicircular path in both directions on the first gimbals, The first gimbals merge at the point where they meet and can extend to the other first drive shaft.

Wherein the second coil extends through a first path that enters from the one first drive shaft and enters the second drive shaft via the first gimbals and forms a first arc type path and then extends outward, Extending through a second path extending inwardly after forming a second arcuate path in a direction opposite to the first arcuate path and extending through a third path opposite the first path to the first drive shaft have.

On one side, the second coil may extend through the first path, then extend through the plurality of second paths, and thereafter extend through the third path.

The first coil may further include a third coil formed in point-symmetry with the second coil with respect to the center of the reflecting surface.

The first gimbals may include a ring-shaped frame, a first arc-shaped frame having a radius larger than that of the ring-shaped frame and having both ends connected to the ring-shaped frame, And a second arc-shaped frame symmetrical with the arc-shaped frame.

On one side, the second drive shaft and the support are located on a straight line, and the first drive shaft can be positioned perpendicular to the second drive shaft.

In one side, a driving force generated by the second coil may drive the second gimbals and the reflection surface together.

And a magnetic body for forming an electromagnetic field together with the coil.

On one side, the magnetic body may include a ring-shaped magnetic body and a cylindrical magnetic body disposed apart from the inside of the ring-shaped magnetic body.

The scanning micromirror according to an exemplary embodiment may be driven by applying an electromagnetic force driving method using a magnetic field.

The scanning micromirror according to an exemplary embodiment may be capable of driving two degrees of freedom regardless of the driving frequency.

The scanning micromirror according to an embodiment can be driven with two degrees of freedom without resonance driving.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned may be clearly understood by those skilled in the art from the following description.

1 is a perspective view illustrating a scanning micromirror according to an embodiment of the present invention.
2 is a view showing the arrangement of the first coil according to one embodiment.
3 is a diagram showing the arrangement of the first coil and the magnetic body.
Figure 4 illustrates the arrangement of a second coil and a third coil in accordance with one embodiment.
Fig. 5 shows a form in which the action of the current in the second coil and the third coil is canceled.
6 illustrates a second gimbals according to one embodiment.
Fig. 7 shows the flow of current and the arrangement of the magnetic body according to the arrangement of the second coil and the third coil.
8 is a view showing an arrangement of a second coil and a third coil according to another embodiment
9 is a view schematically showing the arrangement of the second coil and the third coil according to another embodiment.
10 illustrates a driving mode of a scanning micro-mirror according to an embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, configurations and applications according to embodiments will be described in detail with reference to the accompanying drawings. The following description is one of many possible claims, and the following description forms part of the detailed description of the present invention.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather clear.

1 is a perspective view showing a scanning micromirror 1 according to an embodiment. Referring to FIG. 1, the scanning micromirror 1 according to an embodiment may include a first gimbal 110, a second gimbal 120, a reflecting surface 130, and a coil 300.

The first gimbals 110 may be formed in a ring shape. The first driving shaft 210 may be disposed on both sides of the first gimbals 110. The first drive shaft 210 disposed on both sides of the first gimbals 110 may extend in the circumferential direction of the first gimbals 110. One side of the first driving shaft 210 may be connected to the first gimbals 110 and the other side may be fixed.

The first drive shaft 210 may be formed of an elastic body. Therefore, when the first gimbals 110 are rotated to be driven by the torque, the first drive shaft 210 can support the rotation of the first gimbals 110. That is, the first gimbals 110 can be rotationally driven with the first drive shaft 210 as a rotation axis.

The second gimbals 120 may be coupled to the first gimbals 110 through the second drive shaft 220. The second driving shaft 220 may be disposed perpendicularly to the first driving shaft 210 and may be disposed on both sides of the second gimbals 120. One side of the second driving shaft 220 may be connected to the first gimbals 110 and the other side of the second driving shaft 220 may be connected to the second gimbals 120.

The second drive shaft 220 may be formed of an elastic body. Accordingly, the second gimbals 120 can be rotationally driven with the second drive shaft 220 as a rotation axis.

The reflecting surface 130 may be coupled to the inside of the second gimbals 120 through the support 230. The support 230 can fix the reflecting surface 130. The support 230 may be positioned in a straight line with the second drive shaft 220. One side of the support body 230 may be connected to the second gimbals 120 and the other side may be connected to the reflection surface 130.

The reflecting surface 130 may be formed as a laminated structure including a metal and a dielectric. It is possible to form a convex structure in which the entire surface is uniform in thickness or the center portion is thicker than the outer portion.

The shapes of the first gimbals 110, the second gimbals 120, and the reflecting surface 130 are not limited to the above. May be circular, elliptical, square, or polygonal depending on the embodiment.

The shape of the first drive shaft 210, the second drive shaft 220 or the support body 230 is not limited and may be a cantilever, a torsion beam, a meander beam, or the like. Lt; / RTI >

The coil 300 may be formed on the first gimbals 110 or the second gimbals 120. A magnetic body (not shown) may be disposed on the bottom surface of the scanning micro-mirror 1. When an electric current is supplied to the coil 300, interaction with the magnetic field constituted by the magnetic body may be caused and a force may be generated. The generated force may act as a driving force for generating a torque in the first gimbals 110 or the second gimbals 120 to induce rotational driving of the first gimbals 110 or the second gimbals 120.

A plurality of coils 300 may be provided. Each of the coils may generate a driving force that causes rotational driving using the first driving shaft 210 as a driving shaft and rotational driving using the second driving shaft 220 as a driving shaft. This arrangement of the coils 300 makes it possible to drive two degrees of freedom.

Hereinafter, the arrangement of the coil 300 and the magnetic body and the driving of the first gimbals 110 and the second gimbles 120 will be described.

2 is a view showing the arrangement of the first coil according to one embodiment. Fig. 3 shows the arrangement of the first coil and the magnetic body.

Referring to FIG. 2, the first coil 310 may be formed on the first gimbals 110. The first coil 310 may enter from one side first driving shaft 210a. The first coil 310 may be branched in both directions at the point where the first drive shaft 210 and the first gimbals 110 meet. The branched first coil 310 may extend in a semi-circular path in both directions on the first gimbals 110. The extended first coil 310 may be coupled at the point where the first side drive shaft 210b and the first gimble 110 meet and may extend to the other side first drive shaft 210b. In other words, the first coil 310 may be configured so that the first coil 310 enters the first drive shaft 210a and the second coil 210b moves to the first drive shaft 210b.

Referring to FIG. 3, the magnetic body 400 may be disposed on the bottom surface of the reflection surface 130. The magnetic body 400 may form a radial magnetic field (Hr) directed from the center to the outside.

The magnetic body 400 may include a ring-shaped magnetic body 410 and a cylindrical magnetic body 420 spaced apart from inside the ring-shaped magnetic body. The ring-shaped magnetic body 410 and the cylindrical magnetic body 420 can be magnetized in opposite directions.

The support base 430 may be combined with and support the ring-shaped magnetic body 410 or the cylindrical magnetic body 420. The support base 430 may have a columnar shape with a circular cross section. The support member 430 may include a pole piece or a back iron. As the support member 430, a material such as pure iron having a high relative permeability may be used. With this configuration, an effect of maximizing the radial magnetic field can be obtained.

When the current Ia flows into the first coil 310, the current Ia is branched from one side in both directions and proceeds in a semicircular shape and can be coupled at the other side. At this time, an electromagnetic force F is generated by the current Ia and the radial magnetic field Hr, and thus a rotational torque T can be generated.

That is, when a current flows through the first coil 310, the first gimbals 110 can be rotationally driven with the first drive shaft 210 as a rotation axis.

4 shows the arrangement of the second coil 320 and the third coil 330 according to an embodiment and Fig. 5 shows the arrangement of the second coil 320 and the third coil 330, Lt; / RTI > FIG. 6 shows a second gimbals 120 according to an embodiment, and FIG. 7 shows the flow of current and the arrangement of the magnetic bodies according to the arrangement of the second coil 320 and the third coil 330. FIG.

Referring to FIG. 4, a second coil 320 may be formed on the first gimbals 110 and the second gimbals 120. The second coil 320 may be formed along the first paths 210a, 321, 322, the second paths 323, 324, 325, 326, and the third paths 327, 328, 210a.

First, the second coil 320 may enter from the one first driving shaft 210a and extend in an arc shape along the first gimbals 110 (321). The extended second coil 320 may be advanced 322 along the second drive shaft 220 at a point where the first gimbals 110 and the second drive shaft 220 meet.

Next, referring to the second path, the second coil 320 can form a first arc-shaped path 323 that surrounds the reflecting surface 130 and is semicircular. The second arc-shaped path 325 can then be extended (324) to the outside of the second gimbals 120 and in the opposite direction to the first arc-shaped path 323. At this time, the radius of the second arc-shaped path 325 may be larger than the radius of the first arc-shaped path 323. A second coil 320 extending along the second arcuate path 325 may extend 326 into the second gimbals.

Next, referring to the third path, the second coil 320 formed along the second path may extend through the third path. The third path may be formed opposite to the first path.

That is, the second coil 320 extends along the second path along the second drive shaft 220 to the outside of the second gimbals 327, extends through the first gimbals 110 in an arc shape, May extend to the first drive shaft 210a. The coil extending in the third path may be similar in shape to the coil extending in the first path.

In general, the second coil 320 entering from the first drive shaft 210a may be formed so as to exit to the first drive shaft 210a again.

The scanning micrometer may further include a third coil 330. The third coil 330 may be point-symmetrically formed with respect to the second coil 320 with respect to the center O of the reflecting surface 130.

When a current flows into the second coil 320 and the third coil 330, current may flow through the second coil 320 and the third coil 330, respectively. Although the second coil 320 and the third coil 330 are formed in point symmetry, the current direction may be a line symmetry with respect to the second driving axis 220. In other words, the current in the second gimbals 120 may be formed in such a manner that the current flows in both directions and flows in a semicircular shape.

A magnetic body (not shown) may be disposed on the bottom surface of the reflection surface, and an electromagnetic force may be generated by the current and the radial magnetic field when the electric current flows.

A current can flow in opposite directions in the first path and the third path. Since the magnitude of the current is the same and opposite to that direction, the same magnitude of torque can act in the opposite direction. Therefore, both torques can be offset from each other. Thus, substantially no torque may be generated in the first path and the third path. In addition, since the current flowing in parallel with the second drive shaft 220 is parallel to the radial magnetic field, torque may not be generated.

Hereinafter, a current for generating a torque will be described.

Referring to FIG. 5, a current for generating a torque in the second gimbal 120 may be simplified as shown in FIG. That is, currents flowing through the first arc-shaped paths 323 and 333 and the second arc-shaped paths 325 and 335 can generate torque.

The shape of the second gimbals will be described before explaining the action of the torque accordingly. Referring to FIG. 6, the second gimbals 120 may be formed corresponding to the arrangement of the second coil 320 and the third coil 330. The second gimbals 120 may include a ring-shaped frame 121, a first arc-shaped frame 122, and a second arc-shaped frame 123.

The ring-shaped frame 121 is adjacent to the reflection surface 130 and can be connected to the support 230 to support the reflection surface 130.

The first arc-shaped frame 122 may be connected to the ring-shaped frame 121 at both ends thereof. The first arc-shaped frame 122 can be formed on the outer side of the ring-shaped frame 121 with a larger radius than the ring- The second arced frame 123 may be formed symmetrically with the first arced frame 122 with respect to the center of the ring shaped frame 121.

This illustrates an exemplary form of the second gimbals 120 and is not intended to limit the shape of the second gimbals 120.

Hereinafter, the currents flowing through the second coil 320 and the third coil 330 and the action of the magnetic body will be described.

Referring to FIG. 7, the magnetic materials 410, 420, and 430 may be disposed on the bottom surface of the reflective surface 130. The magnetic body described above together with the first coil 310 may be disposed.

The electromagnetic force F can be generated by the interaction between the current Ib flowing along the second arc type path 325 of the second coil and the radial magnetic field Hr.

Similarly, the electromagnetic force F 'can be generated by the interaction between the current Ib flowing along the second arc path 335 of the third coil and the radial magnetic field Hr.

Electromagnetic forces F and F 'in opposite directions in the second and third coils can be generated, respectively, and the generated electromagnetic forces can generate the torque T. [ Accordingly, the second gimbals 120 can be rotationally driven with the second driving axis direction as a rotation axis.

At this time, the reflecting surface 130 may be connected to the second gimbals through the supporting member 230, and the reflecting surface 130 may be driven together with the supporting member 230.

Torque can be generated by the current flowing along the first arc-shaped path 323, 333, but the size can be small. Therefore, it can be seen that the torque generated by the current flowing substantially along the second arc path 325, 335 acts on the second gimbals 120.

8 and 9 are views showing the arrangement of the second coil 320 and the third coil 330 according to another embodiment. Since there are similarities with the arrangement according to one embodiment, differences will be mainly described.

Referring to FIG. 8, the second coil 320 may extend through the first path, and then extend through the plurality of second paths. In other words, the second coil 320 can be wound a plurality of times on the second gimbals 120. The number of times the second coil 320 is wound is not limited. The second coil 320 wound plural times along the second path may extend through the third path.

The third coil 330 may be formed in point symmetry with the second coil 320 with respect to the center O of the reflecting surface 130. In this case,

Referring to FIG. 9, the current generating torque on the second gimbals, except for the current for which the generated torque is canceled, can be simplified as shown in FIG. Since the coil is wound a plurality of times, a strong torque can be generated.

10 illustrates a driving mode of a scanning micro-mirror according to an embodiment. 10 (a) shows a state in which the first driving shaft 210 is driven to rotate by the first coil, and FIG. 10 (b) shows a state in which the second driving shaft 220 is driven by the second coil and the third coil As shown in Fig.

Referring to FIG. 10, current may be supplied to the first coil, the second coil, or the third coil to drive the scanning micromirror. A current can be supplied to the first coil to drive the first drive shaft 210 with the rotation axis and a current can be supplied to the second coil or the third coil to drive the second drive shaft 220 with the rotation axis.

It is possible to drive the scanning micrometer in a desired form by controlling the current supply. For example, the first drive shaft 210 and the second drive shaft 220 can be simultaneously driven by supplying current to all the coils

The scanning micromirror according to an exemplary embodiment applies electromagnetic driving using a radial magnetic field, can be driven with two degrees of freedom regardless of the driving frequency, and can be driven with two degrees of freedom without resonance driving.

While one embodiment has been described in conjunction with the accompanying drawings, it is to be understood that such embodiments are for the purpose of facilitating understanding of the invention and are not intended to limit or limit the scope of the invention. Those of ordinary skill in the art will be able to modify or adapt the invention according to one embodiment, and such modifications or applications will fall within the scope of the invention. Accordingly, the scope of the invention should not be limited to the specific embodiments described herein.

The present invention is the result of a research carried out by the Ministry of Industry and Commerce, Ministry of Commerce, Industry and Energy (No. 10047785, Development of Smart pico projector parts and engine for 3D HD video).

110 1st Gimble
120 Second Gimble
130 Reflective surface
210 First drive shaft
220 second drive shaft
230 support
310 first coil
320 second coil
330 third coil

Claims (10)

A first gimbals driven with the first drive shaft as a rotation axis;
A second gimble coupled to the first gimble via a second drive shaft and driven by a second drive shaft as a rotation axis;
A reflecting surface coupled to the inside of the second gimbals through a support;
A first coil generating a driving force for driving the first gimbals; And
A second coil generating a driving force for driving the second gimbals;
And a scanning micromirror.
The method according to claim 1,
The first coil enters from one side first drive shaft and branches at a point where the first drive shaft meets the first gimbals. The first coil forms a semicircular path in both directions on the first gimbals, and then the other first drive shaft meets the first gimbals And the scanning micromirror extends to the other first driving shaft.
The method according to claim 1,
The second coil extends through a first path entering from the one first drive shaft to the second drive shaft via the first gimbals,
A second arcuate path extending outwardly from the first arcuate path and extending inwardly after forming a second arcuate path in a direction opposite to the first arcuate path,
And extends to the first drive shaft through a third path opposite to the first path.
The method of claim 3,
Wherein the second coil extends through a first path and then through a plurality of second paths and thereafter extends through the third path.
The method according to claim 1,
And a third coil formed in point-symmetry with the second coil with respect to a central portion of the reflective surface.
The method according to claim 1,
The second gimbals,
Ring type frame;
A first arc-shaped frame having a radius larger than that of the ring-shaped frame and having both ends connected to the ring-shaped frame, respectively; And
A second arc-shaped frame symmetrical with the first arc-shaped frame with respect to the center of the ring-shaped frame;
And a scanning micromirror.
The method according to claim 1,
Wherein the second drive shaft and the support are positioned on a straight line, and the first drive shaft is positioned perpendicular to the second drive shaft.
The method according to claim 1,
And the driving force generated by the second coil drives the second gimbals and the reflecting surface together.
The method according to claim 1,
And a magnetic body that forms an electromagnetic field together with the coil.
10. The method of claim 9,
Wherein the magnetic body includes a ring-shaped magnetic body and a cylindrical magnetic body disposed apart from the inside of the ring-shaped magnetic body.

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