Micromechanical optical element having a reflective surface as well as its use

• US 20070017994A1
• Filed: 07/13/2006
• Published: 01/25/2007
• Est. Priority Date: 07/13/2005
• Status: Active Grant

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Wolter, Alexander, Klose, Thomas
• Granted Patent: US 7,369,288 B2
• Time in Patent Office: Days
• US Class Current: 235/462.370
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81B 3/007 For controlling stiffness, e.g. ribs
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 26/085 the reflecting means being moved or deformed by electromagnetic means

Abstract

By way of example, in this example of the invention, it would also be possible to dispense in a manner which is not illustrated with the spring elements 2, and then for the element 1 to carry out an oscillating translational deflection. The invention relates to micromechanical optical elements having a reflective surface which can be deflected electrostatically or electromagnetically in a known manner and which can be used for a large number of applications. The object of the invention is to provide an element such as this at low cost and with improved dynamic deformation behaviour. The elements according to the invention with a reflective surface are in this case held by spring elements, in which case the element which can be deflected is held on mutually opposite sides by in each case at least two mutually independent spring elements.

Claims

1. Micromechanical optical element having a reflective surface, which can be deflected by means of electrostatic or electromagnetic forces and is held by means of spring elements,

characterized in that the element which can be deflected is held on mutually opposite sides by in each case at least two mutually independent spring elements.

2. Element according to claim 1, characterized in that at least one of the spring elements acts on the element which can be deflected, at least two points at a distance from one another.

3. Element according to claim 1, characterized in that one spring element in each case acts on the element which can be deflected on one axis, and at least two further spring elements act on the element which can be deflected, at constant distances from this.

4. Element according to claim 1, characterized in that the element can be pivoted about one axis.

5. Element according to claim 1, characterized in that an electrostatic comb drive is provided for deflection.

6. Element according to claim 1, characterized in that the points of action of spring elements are arranged at equal distances from one another.

7. Element according to claim 1, characterized in that the points of action of spring elements are arranged symmetrically.

8. Element according to claim 1, characterized in that points of action of spring elements are arranged distributed over the entire circumference of the element which can be deflected.

9. Element according to claim 1, characterized in that points of action of spring elements act on rear-face stiffening elements of the element which can be deflected.

10. Element according to claim 1, characterized in that the spring elements are in the form of at least one of bending springs and bending torsion springs.

11. Element according to claim 1, characterized in that spring elements have different spring constants taking into account the distance between their respective points of action and the rotation axis of the element which can be deflected.

12. Element according to claim 1, characterized in that no point of action of any of the spring elements is arranged on the rotation axis of the element which can be deflected.

13. Element according to claim 1, characterized in that two of the spring elements which are arranged mutually opposite are connected to one another.

14. Use of an element according to claim 1, for deflection elements for laser beams or light beams, in bar-code readers, in projection displays, retina scanning displays, readers for patterns and images, in test equipment, in laser printers or direct exposure devices.