CN112578554A

CN112578554A - Micro-mirror device and projection equipment

Info

Publication number: CN112578554A
Application number: CN202011531949.6A
Authority: CN
Inventors: 陈飞
Original assignee: Shenzhen Zhongkechuang Laser Technology Co ltd
Current assignee: Shenzhen Zhongkechuang Laser Technology Co ltd
Priority date: 2020-12-22
Filing date: 2020-12-22
Publication date: 2021-03-30

Abstract

The application discloses a micro-mirror device and projection equipment, relates to the technical field of micro-mirrors, and aims to solve the problem that a micro-mirror unit in the micro-mirror device in the related art occupies a large space. The micro-mirror device comprises a mounting surface, a support, a micro-mirror and a driving device. The mounting seat comprises a mounting surface, the support is arranged on the mounting surface, the micro mirror is obliquely arranged relative to the mounting surface and is rotatably connected with the support through a rotating shaft, the rotating shaft is arranged at the center of the micro mirror and is perpendicular to the mounting surface, and the driving device is configured to drive the micro mirror to rotate relative to the support. The application can be used in a projection device.

Description

Micro-mirror device and projection equipment

Technical Field

The application relates to the technical field of micro mirrors, in particular to a micro mirror device and projection equipment.

Background

A micromirror device is a MEMS (micro electro mechanical system) device, and its basic principle is that a movable micromirror surface is rotated by a driving force, thereby changing the propagation direction or phase of an input light. Micromirror devices have been widely used in various fields such as optical switching, spectral analyzers, and projection imaging in optical communications.

Disclosure of Invention

Embodiments of the present application provide a micromirror device and a projection apparatus, which are used to solve the problem that a micromirror unit in the micromirror device in the related art occupies a large space.

To achieve the above object, in a first aspect, embodiments of the present application provide a micromirror device including a mounting surface, a support, a micromirror and a driving apparatus. The mount includes a mounting surface. The bracket is arranged on the mounting surface. The micro-mirror is obliquely arranged relative to the mounting surface and is rotatably connected with the bracket through a rotating shaft, and the rotating shaft is arranged at the center of the micro-mirror and is vertical to the mounting surface. The driving device is configured to drive the micro mirror to rotate relative to the support.

In a second aspect, an embodiment of the present application provides a projection apparatus, which includes a projection lens, a projection light source, and the micro mirror device in the first aspect, wherein the micro mirror of the micro mirror device is configured to reflect a light beam emitted by the projection light source into the projection lens or out of the projection lens.

The micro mirror device and the projection equipment provided by the embodiment of the application are characterized in that the micro mirror is rotatably arranged on the support through the rotating shaft, the rotating shaft is arranged at the center of the micro mirror and is vertical to the mounting surface, namely: the support is located between the micro-mirror and the mounting surface, so that the support can fully utilize the space between the micro-mirror and the mounting surface, the occupation of the peripheral space of the micro-mirror is greatly reduced, the occupation space of the micro-mirror unit on the mounting surface is favorably reduced, the number of the micro-mirror units on the mounting seat can be increased, and the increase of the number of the micro-mirror units is favorable for improving the quality of the projected picture of the projection equipment.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a projection device in some embodiments of the present application;

FIG. 2 is a schematic diagram of a micro-mirror device according to the related art;

FIG. 3 is a schematic diagram of a micromirror device in some embodiments of the present application;

FIG. 4 is a side view of the micromirror device shown in FIG. 3;

fig. 5 is a schematic structural diagram of a micromirror unit cell in some embodiments of the present application;

FIG. 6 is a longitudinal cross-sectional view of FIG. 5;

FIG. 7 is a schematic illustration of the structure of a stent according to some embodiments of the present application;

FIG. 8 is a schematic diagram of the positions of the driving devices on the mounting base and the micro-mirror according to some embodiments of the present application;

FIG. 9 is a schematic view of a micromirror electrode and a mount electrode structure according to some embodiments of the present application;

FIG. 10 is a schematic view of a micromirror electrode and a mount electrode structure according to other embodiments of the present application;

FIG. 11 is a schematic view of a micromirror electrode and a mount electrode structure according to other embodiments of the present application;

FIG. 12 is a schematic view of the electrode structure of the micromirror and the electrode structure of the mounting seat in other embodiments of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; the specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

Fig. 1 is a schematic diagram of a projection device in some embodiments of the present application, as shown in fig. 1. The projection apparatus includes a projection light source 100, a color wheel 200, a light collecting rod 300, a relay optical system 400, a mirror 500, a TIR (Total Internal Reflection) prism set 600, a micro-mirror device 700, and a projection lens 800. Wherein the relay optical system 400 comprises two convex lenses.

The working principle of the projection equipment is as follows: white light generated by the projection light source 100 is divided into red, green and blue tricolor light by the color wheel 200, the tricolor light is projected onto the micromirror device 700 after passing through the light collecting rod 300, the relay optical system 400, the reflecting mirror 500 and the TIR prism group 600, the micromirror device 700 includes a plurality of micromirrors, one micromirror is equivalent to one pixel unit, each micromirror can rotate a certain angle, signal input is processed and then acted on the micromirror device 700, thereby controlling the rotation of the micromirror, along with the difference of the rotation angle of the micromirror, a light beam may be reflected into the projection lens 800 or outside the projection lens 800, specifically: when the micro-mirrors are in an on state, light beams are reflected by the micro-mirrors into the projection lens 800; when the micro-mirrors are in the off-state, the light beam is reflected by the micro-mirrors to other places and does not enter the projection lens 800, and the light beam is selectively reflected by the micro-mirrors of the micro-mirror device 700 and is projected and imaged by the projection lens 800.

The projection light source 100 may be a laser light source, or may be other types of light sources, and is not limited in particular. The micromirror device 700 may be used in other optical systems besides the projection apparatus, and is not limited in detail herein.

In a possible implementation manner, the projection light source 100 may be a light source composed of three-color laser tubes of red, green, and blue, so that the three primary colors may enter the light collecting rod 300 after being mixed by the light combining system, and by this way, the use of the color wheel 200 may be eliminated, thereby saving the volume of the projection device and avoiding the attenuation of the color wheel to the light source; on the other hand, the laser tube has a longer light-emitting life, and the service life of the projection equipment can be prolonged.

As shown in fig. 2, fig. 2 is a schematic structural diagram of a micromirror device 700 in the related art. The micromirror device 700 includes a mounting base 1 and a plurality of micromirror units 2, the mounting base 1 is plate-shaped and includes a mounting surface 11, and the micromirror units 2 are disposed on the mounting surface 11 and arranged in an array.

The micromirror unit 2 includes a holder 3, micromirrors 4, and a hinge 5. The bracket 3 is cylindrical, the micro-reflector 4 is rotatably arranged on the bracket 3 through a rotating shaft 5, and the rotating shaft 5 is parallel to the mounting surface 11. The micromirrors 4 may control the reflection paths of the light beams by flipping.

In the micromirror device 700, since the rotating shaft 5 is parallel to the mounting surface 11, to ensure the rotatable connection between the rotating shaft 5 and the bracket 3, the bracket 3 needs to be disposed at the periphery of the micromirror 4, and thus the bracket 3 needs to occupy a part of the peripheral space of the micromirror 4, so that the occupied space of each micromirror unit 2 is relatively large, thereby limiting the number of micromirrors 4 mounted on the mounting base 1 (that is, the number of "pixels" of the micromirror device 700 is reduced), and further affecting the quality of the image projected by the projection apparatus.

As shown in fig. 3 and 4, fig. 3 is a schematic structural diagram of a micromirror device 700 in some embodiments of the present application, and fig. 4 is a side view of the micromirror device 700 shown in fig. 3. The micromirror device 700 includes a mounting seat 1 and a plurality of micromirror units 2, the mounting seat 1 is plate-shaped, the mounting seat 1 includes a mounting surface 11, the micromirror units 2 are arranged on the mounting surface 11 and are arranged in a 3 × 5 (row × column) array (that is, the micromirror units 4 are arranged in a 3 × 5 array).

The number of the micromirror units 2 may be determined according to actual conditions, and the micromirror units 2 are not limited to be arranged in a 3 × 5 array, and may also be arranged in a ring array, etc., and is not specifically limited herein; the mount 1 may be in the form of a plate, or may be in the form of other shapes, and is not limited in particular.

As shown in fig. 5 and 6, fig. 5 is a schematic structural view of a micromirror unit 2 in some embodiments of the present application, and fig. 6 is a longitudinal sectional view of fig. 5. The micromirror unit 2 includes a support 3, a micromirror 4, and a driving device 6, and the support 3 is rod-shaped and is disposed on the mounting surface 11. The micro-mirror 4 is obliquely arranged relative to the mounting surface 11 and is rotatably connected with the bracket 3 through the rotating shaft 5. The rotation shaft 5 is disposed at the center of the micromirror 4 and is perpendicular to the mounting surface 11. The driving means 6 are configured to drive the micromirror 4 to rotate around the rotation axis 5.

The "vertical" in the vertical direction of the rotating shaft 5 and the mounting surface 11 includes not only absolute vertical but also approximate vertical due to mounting error; the micro-mirror 4 may be tilted at an angle of 15 degrees relative to the mounting surface 11.

When the micro-mirror device works, the driving device 6 can drive the micro-mirror 4 to rotate according to actual conditions, and as the rotating shaft 5 is vertical to the mounting surface 11, the micro-mirror 4 is obliquely arranged relative to the mounting surface 11, so that when the micro-mirror 4 rotates around the rotating shaft 5, the position of the reflecting surface of the micro-mirror 4 can be changed, and the reflecting path of light can be changed.

In the micromirror device 700 described above, since the micromirror 4 is rotatably disposed on the support 3 by the rotation shaft 5, the rotation shaft 5 is disposed at the center of the micromirror 4 and perpendicular to the mounting surface 11, that is: the bracket 3 is located between the micro-mirror 4 and the mounting surface 11, so that the bracket 3 can fully utilize the space between the micro-mirror 4 and the mounting surface 11, the occupation of the peripheral space of the micro-mirror 4 is greatly reduced, the occupation space of the micro-mirror unit 2 on the mounting surface 11 is favorably reduced, the number of the micro-mirror units 2 on the mounting base 1 can be increased, and the increase of the number of the micro-mirror units 2 (equivalent to the increase of the 'pixels' of the micro-mirror device 700) is favorable for improving the quality of the picture projected by the projection equipment.

In some embodiments, as shown in fig. 7, fig. 7 is a schematic view of another configuration of the stent 3. The bracket 3 comprises a first rod-shaped subframe 31 and a second rod-shaped subframe 32, the first subframe 31 is arranged on the mounting surface 11, the second subframe 32 is arranged on the first subframe 31, and the micro mirror 4 is rotatably connected with the second subframe 32 through the rotating shaft 5. The cross-sectional area of the first sub-frame 31 is larger than the cross-sectional area of the second sub-frame 32. By designing the cross-sectional area of the first sub-frame 31 to be larger, the connection strength with the mounting surface 11 can be improved, and the stability of the micromirror 4 can be ensured.

In some embodiments, as shown in fig. 3 and 4, the orthographic projections of two adjacent micro-mirrors 4 on the mounting surface 11 have a portion overlapping. Thus, light can be prevented from leaking out from the gap between two adjacent micro mirrors 4, so that the reflectivity of the micro mirror device 700 to light is increased, and the utilization rate of the micro mirror device 700 to light intensity or light source brightness is increased.

In some embodiments, as shown in fig. 3 and 4, in two adjacent micromirrors 4, the height of the support 3 to which one micromirror 4 is connected is greater than the height of the support 3 to which the other micromirror 4 is connected. By this arrangement, two adjacent micromirrors 4 can be shifted in the height direction of the support 3 to avoid the interference of movement of the two adjacent micromirrors 4 during rotation.

As shown in fig. 3 and 4, the micromirrors 4 in the same row or column may be arranged in a staggered manner. In addition, the device may be arranged in a gradually increasing or decreasing manner, and is not particularly limited herein.

The structure of the driving device 6 is not exclusive, and in some embodiments, the driving device 6 may be a micro motor disposed on the bracket 3, and an output shaft of the micro motor is connected to the rotating shaft 5.

In other embodiments, as shown in fig. 6 and 8, fig. 8 is a schematic diagram of the positions of the driving devices 6 on the mounting base 1 and the micro-mirrors 4, and the dotted lines on the mounting surface 11 in fig. 8 are contour lines of the projection of the micro-mirrors 4 on the mounting surface 11.

Driving device 6 includes micromirror electrode 61 and mount electrode 62, micromirror electrode 61 being disposed on micromirror 4, specifically, micromirror electrode 61 being disposed on the back surface of micromirror 4. Mount electrode 62 is disposed on mounting surface 11, and an attractive force is generated between mount electrode 62 and micromirror electrode 61 to drive micromirror 4 to rotate relative to holder 3. The provision of driver 6 as micromirror electrode 61 and mount electrode 62, as compared to the micro motor, eliminates the need to mount a micro motor on each support 3, thereby contributing to a reduction in cost of micromirror device 700.

In some embodiments, as shown in fig. 9, (a) in fig. 9 is a schematic diagram of the arrangement position of the micromirror electrode 61 on the micromirror 4, (b) in fig. 9 is a relationship between the orthographic projection 61a of the micromirror 4 on the mounting surface 11 and the mount electrode 62, and the dotted line is the micromirror 4 and the projection of the micromirror electrode 61 on the mounting surface 11.

The mount electrode 62 is disposed in the micromirror projection area 12, and the micromirror projection area 12 is an orthographic projection of the micromirror 4 on the mounting surface 11. In the circumferential direction of micromirror projection area 12, the orthographic projection 61a of micromirror electrode 61 on mounting surface 11 is offset from mount pad electrode 62.

Here, the orthographic projection of the micromirror 4 on the mounting surface 11 is the orthographic projection of the micromirror 4 on the mounting surface 11 in the initial state. The orthographic projection 61a of the micromirror electrode 61 on the mounting surface 11 is the orthographic projection of the micromirror electrode 61 on the mounting surface 11 in the initial state of the micromirror 4. The "initial state" may be an on state, an off state, or other intermediate states of the micromirror 4, and is not particularly limited herein.

By offsetting the orthographic projection 61a of micromirror electrode 61 on the mounting surface 11 from the mount electrode 62 in the circumferential direction of the micromirror projection area 12, the component force of the attractive force between the mount electrode 62 and the micromirror electrode 61 in the tangential direction of the micromirror 4 is larger, so that the micromirror 4 can be more easily driven to rotate about the rotation axis 5.

In some embodiments, as shown in fig. 6 and 8, micromirror electrodes 61 are disposed at the edges of the micromirror 4. Thus, when micromirror 4 is driven to rotate, the attractive force between micromirror electrode 61 and mount electrode 62 acts on the edge of micromirror 4, which generates a greater moment of rotation, thereby making the rotation of micromirror 4 easier.

Wherein, as shown in fig. 6 and 8, the mount electrode 62 can be disposed at the edge of the micro-mirror projection area 12. This may cause mount electrode 62 to be closer to micromirror electrode 61, thereby causing a greater attractive force between micromirror electrode 61 and mount electrode 62 to facilitate the rotation of micromirror 4.

In some embodiments, as shown in fig. 9, the number of micromirror electrodes 61 is multiple, and the multiple micromirror electrodes 61 are spaced and uniformly arranged along the circumference of the micromirror 4. The number of mount electrodes 62 is plural, and the plural mount electrodes 62 are spaced and uniformly arranged along the circumference of micro-mirror projection area 12. The orthographic projection 61a of each micromirror electrode 61 on the mounting surface 11 is offset from the corresponding mount electrode 62 along the circumference of the micromirror projection area 12. By providing a plurality of micromirror electrodes 61 and a plurality of mount electrodes 62, in operation, the attractive force between micromirror electrodes 61 and mount electrodes 62 can act on micromirror 4 uniformly in the circumferential direction, so that the rotation of micromirror 4 can be made more smooth.

The number of the mount electrodes 62 and the micromirror electrodes 61 may be 2, 3, 4, etc., and is not limited herein.

The shapes of micromirror electrode 61 and mount electrode 62 are not exclusive, and in some embodiments, micromirror electrode 61 and mount electrode 62 are both linear electrodes as shown in fig. 9. The micromirror electrode 61 and the mount pad electrode 62 are arranged as linear electrodes, so that the occupied space of the micromirror electrode 61 and the mount pad electrode 62 is small, and the arrangement of the micromirror electrode 61 and the mount pad electrode 62 is convenient.

In other embodiments, as shown in FIG. 10, micromirror electrode 61 and mount electrode 62 are bulk electrodes. By arranging micromirror electrode 61 and mount electrode 62 as bulk electrodes, the volume of micromirror electrode 61 and mount electrode 62 can be made larger, and more electric charges can be stored in micromirror electrode 61 and mount electrode 62, so that the attractive force between micromirror electrode 61 and mount electrode 62 can be made larger, and the rotation of micromirror 4 can be driven more easily.

In other embodiments, as shown in fig. 11, micromirror electrode 61 and mount electrode 62 are electromagnetic coils, and by configuring micromirror electrode 61 and mount electrode 62 as electromagnetic coils, the direction of current applied to micromirror electrode 61 and mount electrode 62 can be controlled to control the attraction or repulsion between them, so that the rotation of micromirror 4 can be driven by either attraction or repulsion, thereby making the control of micromirror 4 more flexible.

The micro mirror 4 may have a circular shape, a square shape, a diamond shape, etc., and is not particularly limited thereto.

When micromirror 4 is circular, micromirror electrode 61 and mount electrode 62 are both circular arc-shaped as shown in fig. 8, 9 and 11. Thus, the micromirror electrode 61 and the mount electrode 62 can be better matched with the shape of the micromirror 4, and when in operation, the attractive force generated by the micromirror electrode 61 and the mount electrode 62 can act on the micromirror 4 along the circumferential direction of the micromirror 4, thereby being more beneficial to driving the micromirror 4 to rotate.

In the description herein, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A micro mirror device, comprising:

a mount including a mounting surface;

the bracket is arranged on the mounting surface;

the micro-mirror is obliquely arranged relative to the mounting surface and is rotatably connected with the bracket through a rotating shaft, and the rotating shaft is arranged at the center of the micro-mirror and is vertical to the mounting surface;

a driving device configured to drive the micromirror to rotate relative to the support.

2. The micro-mirror device of claim 1,

the driving device includes:

a micromirror electrode disposed on the micromirror;

the mounting seat electrode is arranged on the mounting surface, and attractive force can be generated between the mounting seat electrode and the micro-mirror electrode so as to drive the micro-mirror to rotate relative to the support.

3. The micro-mirror device of claim 2,

the mounting seat electrode is arranged in a micro-mirror projection area, and the micro-mirror projection area is the orthographic projection of the micro-mirror on the mounting surface;

and along the circumferential direction of the projection area of the micro-mirror, the orthographic projection of the micro-mirror electrode on the mounting surface is staggered with the mounting seat electrode.

4. The micro-mirror device of claim 3,

the number of the micromirror electrodes is multiple, and the micromirror electrodes are uniformly distributed at intervals along the circumferential direction of the micromirror;

the number of the mounting seat electrodes is multiple, and the multiple mounting seat electrodes are uniformly distributed at intervals along the circumferential direction of the projection area of the micro mirror;

and along the circumferential direction of the projection area of the micro-mirrors, the orthographic projection of each micro-mirror electrode on the mounting surface is staggered with the corresponding mounting seat electrode.

5. The micro-mirror device of claim 2,

the micromirror electrode and the mounting base electrode are respectively one of an electromagnetic coil, a linear electrode and a block electrode.

6. The micro-mirror device of claim 2,

the micro reflector is circular;

the micromirror electrode and the mounting seat electrode are both arc-shaped.

7. The micro-mirror device of claim 2,

the micro-mirror electrode is arranged at the edge of the micro-mirror.

8. The micro-mirror device according to any of claims 1 to 7,

the number of the micro mirrors is multiple, the micro mirrors are arranged in an array, and partial orthographic projections of the two adjacent micro mirrors on the mounting surface are overlapped.

9. The micro-mirror device of claim 8,

in two adjacent micro mirrors, the height of the support connected with one micro mirror is larger than that of the support connected with the other micro mirror.

10. A projection device, comprising:

a projection lens;

a projection light source;

the micro-mirror device of any of claims 1-9, wherein the micro-mirrors of the micro-mirror device are configured to reflect light beams emitted by the projection light source into or out of the projection lens.