Micromirror arrangement

Patent metadata

Field	Value
Publication number	US-9753280-B2
Application number	US-201415037509-A
Country	US
Kind code	B2
Filing date	Nov 24, 2014
Priority date	Nov 22, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

What is proposed is: a micromirror arrangement which comprises: a first spring-mass oscillator, which has an oscillatory body forming a mirror plate ( 1 ) and first spring elements ( 2 ); a second spring-mass oscillator, which has a drive plate ( 3 ) and second spring elements ( 4 ) and which is connected to a carrier arrangement ( 5, 8, 9 ) via the second spring elements ( 4 ), wherein the first spring-mass oscillator is suspended in the second spring-mass oscillator via the first spring elements ( 2 ); and a drive arrangement ( 11 ), which is assigned to the drive plate and is designed to cause the drive plate ( 3 ) to oscillate. The oscillatory body ( 1 ) is suspended, movably on two axes, via the first spring elements ( 2 ) on the drive plate ( 3 ), and the drive plate ( 3 ) is connected, movably on two axes, to the carrier arrangement ( 5, 8, 9 ), wherein the drive arrangement ( 11 ) is embodied as a two-axis drive and is designed to drive the drive plate ( 3 ) on two axes such that the oscillatory body ( 1 ) oscillates on two axes at in each case one of its orthogonal eigenmodes or close to this eigenmode.

First claim

The invention claimed is:

1. A micromirror arrangement comprising
a first spring-mass oscillator comprising an oscillation body forming a mirror plate, and comprising first spring elements;
a second spring-mass oscillator which comprises a drive plate and second spring elements and is connected to a carrier arrangement via the second spring elements,
wherein the first spring-mass oscillator is suspended in the second spring-mass oscillator via the first spring elements, and
a drive arrangement which is assigned to the drive plate and is designed to excite the drive plate into oscillation,
characterised in that the oscillation body is movably suspended on the drive plate in a biaxial manner via the first spring elements, and the drive plate is connected to the carrier arrangement in a biaxially movable manner,
wherein the drive arrangement is designed as a biaxial drive and is designed to drive the drive plate in a biaxial manner such that the oscillation body oscillates in a biaxial manner in each case with one of its orthogonal eigenmodes or close to these eigenmodes,
the drive plate is designed as several drive plate segments, which simultaneously form the second spring elements and
the oscillation body is suspended on the drive plate via at least two, preferably three, four or more spring elements which are designed as annular spring frames and which form a cardanic suspension.

2. The micromirror arrangement according to claim 1 , wherein the drive arrangement is designed to drive the drive plate in a manner such that the oscillation body and the drive plate oscillate in a counter-phased manner.

3. The micromirror arrangement according to claim 1 , wherein the oscillation body is suspended on the drive plate via three or four discrete first spring elements.

4. The micromirror arrangement according to claim 1 , wherein the drive plate is suspended on the carrier arrangement via at least two, preferably three or four discrete second spring elements or at least two, preferably more spring elements which are designed as annular spring frames.

5. The micromirror arrangement according to claim 1 , wherein the first spring elements are designed as several, preferably three or four or more annular spring frames which are nested in one another, surrounding the oscillation body, and at least two connection locations in each case are connected to the oscillation body, are connected amongst one another and are connected to the drive plate, wherein the connection locations from the oscillation body to the drive plate are offset by an angle between 90 to 120°, preferably 90°.

6. The micromirror arrangement according to claim 1 , wherein the drive arrangement is designed as a biaxial, electrostatic, piezoelectric and/or electromagnetic drive.

7. The micromirror arrangement according to claim 1 , wherein the carrier arrangement comprises a substrate, preferably an electrode chip, and an actuator chip which is fixedly connected via a spacer, with which the spring mass oscillators are fastened on a stationary part, and the carrier arrangement is covered by a cover and, as the case may be, by a base, in a vacuum-tight manner for forming a vacuum-encapsulated micromirror chip, wherein a getter is preferably incorporated into the micromirror chip.

8. The micromirror arrangement according to claim 1 , wherein electrodes and/or piezoelectric elements and/or coils and/or magnetic layers are attached on the carrier arrangement in a manner lying opposite the drive plate segments, and/or are attached on the drive plate segments.

9. The micro mirror arrangement according to claim 1 , wherein the electrodes which serve as position detection elements and phase detection elements for determining the phase and the position of the drive plate are attached on the carrier arrangement of the drive plate or on the drive plate elements, at a distance lying opposite the drive plate or drive plate segments.

10. A micromirror arrangement comprising
a first spring-mass oscillator comprising an oscillation body forming a mirror plate, and comprising first spring elements;
a second spring-mass oscillator which comprises a drive plate and second spring elements and is connected to a carrier arrangement via the second spring elements, wherein the first spring-mass oscillator is suspended in the second spring-mass oscillator via the first spring elements, and
a drive arrangement which is assigned to the drive plate and is designed to excite the drive plate into oscillation,
wherein the oscillation body is movably suspended on the drive plate in a biaxial manner via the first spring elements, and the drive plate is connected to the carrier arrangement in a biaxially movable manner,
wherein the drive arrangement is designed as a biaxial drive and is designed to drive the drive plate in a biaxial manner such that the oscillation body oscillates in a biaxial manner in each case with one of its orthogonal eigenmodes or close to these eigenmodes,
the oscillation body is suspended on the drive plate via at least two, preferably three, four or more spring elements which are designed as annular spring frames and which form a cardanic suspension and
the drive plate is suspended on the carrier arrangement via at least two, preferably more spring elements which are designed as annular spring frames surrounding the drive plate.

11. The micromirror arrangement according to claim 10 , wherein the drive plate is designed as a ring frame surrounding the oscillation body.

12. The micromirror arrangement according to claim 10 , wherein the oscillation body is suspended on the drive plate via three or four discrete first spring elements.

13. The micromirror arrangement according to claim 10 , wherein the first spring elements are designed as several, preferably three or four or more annular spring frames which are nested in one another, surrounding the oscillation body, and at least two connection locations in each case are connected to the oscillation body, are connected amongst one another and are connected to the drive plate, wherein the connection locations from the oscillation body to the drive plate are offset by an angle between 90 to 120°, preferably 90°.

14. The micromirror arrangement according to claim 10 , wherein the drive plate is connected to the carrier arrangement via at least two or more spring frames which surround the drive plate, wherein the drive plate is connected to the spring frame directly surrounding it, the spring frames are connected amongst one another and the outermost spring frame connected to the carrier arrangement, via connection locations which are in each case offset by an angle between 90 and 120°, preferably by 90°.

Assignees

• Fraunhofer Ges Forschung

Inventors

• Hofmann Ulrich
• Senger Frank
• Von Wantoch Thomas
• Mallas Christian
• Janes Joachim

Classifications

• B81B2203/0163

  Spring holders · CPC title

• B81B2203/058

  Rotation out of a plane parallel to the substrate · CPC title

• G02B26/0841

  the reflecting element being moved or deformed by electrostatic means · CPC title

• B81B2201/042

  Micromirrors, not used as optical switches · CPC title

• G02B26/101 Primary

  with both horizontal and vertical deflecting means, e.g. raster or XY scanners (colour television using laser beams scanning a display screen H04N9/3129) · CPC title