Planar flexure system with high pitch stiffness
View Patent ↗A flexure system for miniature camera and the like is disclosed. The flexure system can include a frame and a stage that is configured to move with respect to the frame. One or more flexures can interconnect the frame and the stage. Each flexure can have one or more film hinges formed thereon. The film hinges can be widely spaced and/or extended in length so as to substantially mitigate undesirable pitching of the stage.
1. A flexure system for a miniature camera, the flexure system comprising:
a frame;
a stage;
an interconnecting member;
a first film hinge connecting between the frame and a proximal end of the interconnecting member; and
a second film hinge interconnecting between the stage and a distal end of the interconnecting member, wherein the flexure system is formed from a planar wafer having a first thickness such that the frame, the stage, and the interconnecting member are planar and have the first thickness and the first and second film hinges have a second thickness that is less than the first thickness.
2. The flexure system as recited in claim 1 , further comprising a linearizing flexure through which the first film hinge connects to the frame.
3. The flexure system as recited in claim 1 , wherein the first film hinge comprises two first film hinges and the two first film hinges are separated by a distance that is sufficient so as to substantially inhibit pitching of the stage.
4. The flexure system as recited in claim 1 , wherein the second film hinge comprises two second film hinges and the two second film hinges are separated by a distance that is sufficient so as to substantially inhibit pitching of the stage.
5. The flexure system as recited in claim 3 , wherein the two first film hinges are separated by a distance that is greater than one half of a diameter of the stage.
6. The flexure system as recited in claim 4 , wherein the two second film hinges are separated by a distance that is approximately equal to a diameter of the stage.
7. The flexure system as recited in claim 1 , wherein each of the first and second film hinges have a length that is sufficient so as to substantially inhibit pitching of the stage.
8. The flexure system as recited in claim 1 , wherein the frame is generally square.
9. The flexure system as recited in claim 1 , wherein the stage defines a lens mount.
10. The flexure system as recited in claim 1 , wherein the stage defines a lens mount that is disposed generally centrally within the frame.
11. The flexure system as recited in claim 1 , wherein the stage is generally co-planar with respect to the frame.
12. The flexure system as recited in claim 1 , wherein the frame is substantially rigid.
13. The flexure system as recited in claim 1 , wherein the interconnecting member is substantially rigid.
14. The flexure system as recited in claim 1 , wherein the stage is substantially rigid.
15. The flexure system as recited in claim 1 , wherein a spring rate for actuation of the stage in the orthogonal direction is approximately 15 N/m and a spring rate for in-plane movement is approximately 70,000 N/m.
16. The flexure system as recited in claim 1 , wherein the interconnecting member comprises four interconnecting members.
17. The flexure system as recited in claim 1 , wherein the interconnecting member extends radially from the frame to the stage.
18. The flexure system as recited in claim 1 , wherein the wafer is a silicon wafer.