Electro-mechanical designs for MEMS scanning mirrors
View Patent ↗Electro-mechanical designs for MEMS scanning mirrors are described. In various embodiments, a driving coil may be situated on a reflective portion of a MEMS mirror. In some embodiments, a sensing coil may be situated partially or entirely on an outer frame portion of the MEMS mirror. Other embodiments are described and claimed.
1. An apparatus, comprising: a frame; a reflective surface coupled to a portion of the frame, the reflective surface to receive a light beam from a light source; a driving coil coupled to the frame, the driving coil to receive a first electric current to induce movement of at least the portion of the frame about a first axis, the movement to scan the light beam across a projection surface; a sensing coil coupled to the frame, the movement to induce a second electric current in the sensing coil, wherein the second electric current indicates a position of the portion of the frame about the first axis; an outer frame disposed at least partially around the frame; and an outer driving coil coupled to the outer frame, the outer driving coil to receive a third electric current to induce second movement of at least the portion of the frame about a second axis.
2. The apparatus of claim 1 , the driving coil disposed proximate to the reflective surface.
3. The apparatus of claim 2 , wherein the sensing coil is disposed around the driving coil.
4. The apparatus of claim 1 , comprising a substrate, the reflective surface disposed on the substrate and the driving coil embedded into the substrate under the reflective surface.
5. The apparatus of claim 1 , comprising torsion bars to mechanically couple the frame to the outer frame, the torsion bars to provide the induced movement about the first axis.
6. The apparatus of claim 1 , the second electric current to indicate the position of the reflective surface about the first axis and the second axis.
7. The apparatus of claim 1 , wherein a perimeter of at least one of the reflective surface or the frame comprises a square, a rectangle, an oval, a circle, or a polygon.
8. A system comprising:
a light source to emit a light beam; and
a microelectromechanical system (MEMS), the MEMS comprising:
a frame;
a reflective surface coupled to the frame and arranged to receive the light beam;
a driving coil coupled to the frame, the driving coil to receive a first electric current to induce movement of the reflective surface;
a sensing coil coupled to the frame, the movement to induce a second electric current in the sensing coil;
an outer frame disposed at least partially around the frame; and
an outer driving coil coupled to the outer frame, the outer driving coil to receive a third electric current to induce second movement of at least the portion of the frame about a second axis.
9. The system of claim 8 , wherein the movement of the portion of the frame about a first axis and the second electric current indicates a position of the portion of the frame about the first axis.
10. The system of claim 9 , wherein the movement of the reflective surface to scan the light beam across a projection surface.
11. The system of claim 8 , the driving coil disposed proximate to the reflective surface.
12. The system of claim 11 , wherein the sensing coil is disposed around the driving coil.
13. The system of claim 8 , comprising a substrate, the reflective surface disposed on the substrate and the driving coil embedded into the substrate under the reflective surface.
14. The system of claim 8 , comprising torsion bars to mechanically couple the frame to the outer frame, the torsion bars to provide the induced movement about the first axis.
15. The system of claim 8 , the second electric current to indicate the position of the reflective surface about the first axis and the second axis.
16. The system of claim 8 , wherein a perimeter of at least one of the reflective surface or the frame comprises a square, a rectangle, an oval, a circle, or a polygon.