Analog interferometric modulator device

• US 8,008,736 B2
• Filed: 06/03/2005
• Issued: 08/30/2011
• Est. Priority Date: 09/27/2004
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Kothari, Manish
• Primary Examiner(s): Gebremariam; Samuel A
• Application Number:
  US11/144,546
• Publication Number:
  US 20060065940A1
• Time in Patent Office: 2,279 Days
• Field of Search: 359/290, 257/415
• US Class Current: 257/415
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26

Abstract

Disclosed is new architecture of microelectromechanical system (MEMS) device. The device has a partially reflective optical layer, a deformable mechanical layer and a mirror layer, each of which forms an independent electrode. A support post separates the optical layer from the mechanical layer. The mirror layer is located and movable between a first position and a second position, which are located between the optical layer and the mechanical layer. The mirror is spaced from the support post, and mirror is responsive to voltages applied to the three electrodes, thereby moving between the first position and the second position. By applying various combinations of voltage differences between the optical layer and the mirror, and between the mirror and the mechanical layer, the location of the mirror between the first and second positions is tunable throughout the space between the two positions. The tunable MEMS device can be used as an analog display element or analog electrical device such as a tunable capacitor. The MEMS device of the disclosed architecture can also be operated in a non-analog manner.

Claims

1. A microelectromechanical system device comprising:

a first electrode layer;

a second electrode layer, said second electrode layer being deformable;

a support structure which separates the first electrode layer from the second electrode layer;

a reflective element comprising a conductive layer and a reflective surface formed on the conductive layer, the reflective element being movable between a first position and a second position, the first and second positions located between the first and second electrode layers, the conductive layer electrically insulated from the first electrode layer and the second electrode layer, the reflective element spaced apart from the support structure; and

a conductive extension electrically and mechanically connected to said conductive layer, said conductive extension passing through the second electrode layer;

wherein the reflective element is responsive to voltages applied to the first electrode layer, the second electrode layer, and the conductive layer by moving between the first position and the second position, wherein said second electrode layer deforms as the reflective element moves between the first and second positions.

2. The device of claim 1, wherein the conductive layer comprises the reflective layer surface.

3. The device of claim 1, wherein a third position is located between the first and second position, and wherein the reflective element spontaneously moves toward the first position when the reflective element is located between the first position and the third position

4. The device of claim 3, wherein the distance between the first position and the third position is about one-third of the distance between the first electrode layer and the second electrode layer.

5. The device of claim 1, wherein the first electrode layer comprises a partially reflective surface.

6. The device of claim 1, wherein the reflective element is mechanically integrated with the second electrode layer.

7. The device of claim 1, wherein the second electrode layer is deformable as the reflective element moves between the first and second positions.

8. The device of claim 7, wherein the conductive extension mechanically integrates the second electrode layer and the reflective element.

9. The device of claim 8, wherein the conductive extension electrically connects the conductive layer to a voltage source.

10. The device of claim 1, wherein the reflective element is mechanically decoupled from the second electrode layer.

11. The device of claim 10, wherein the conductive extension passes through a hole formed in the second electrode layer, and wherein the conductive extension does not contact the second electrode layer.

12. The device of claim 1, wherein the reflective element is capable of being substantially stationary at any position between the first and second positions.

13. The device of claim 1, further comprising a nonconductive layer between the first electrode layer and the reflective element.

14. The device of claim 1, wherein a location of the reflective element between the first and second positions is tunable by controlling voltage differences applied between the first electrode layer and the conductive layer, and between the second electrode layer and the conductive layer.

15. The device of claim 1, wherein the device comprises a tunable capacitor.

16. The device of claim 1, wherein the device comprises a tunable frequency filter for filtering a frequency component of input signals received through the first electrode layer.

17. The device of claim 1, further comprising:

a display;

a processor that is in electrical communication with said display, said processor being configured to process image data; and

a memory device in electrical communication with said processor.

18. The device of claim 17, further comprising:

a first controller configured to send at least one signal to said display; and

a second controller configured to send at least a portion of said image data to said first controller.

19. The device of claim 17, further comprising an image source module configured to send said image data to said processor.

20. The device of claim 19, wherein said image source module comprises at least one of a receiver, transceiver, and transmitter.

21. The device of claim 17, further comprising an input device configured to receive input data and to communicate said input data to said processor.