Photonic MEMS and structures

• US 8,405,899 B2
• Filed: 07/20/2009
• Issued: 03/26/2013
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Chui, Clarence
• Primary Examiner(s): Lester, Evelyn A.
• Application Number:
  US12/506,089
• Publication Number:
  US 20090279162A1
• Time in Patent Office: 1,345 Days
• Field of Search: 359/223, 359/224, 359290-295, 359/298, 359/315
• US Class Current: 359/290
• 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

An optical device includes a non-transparent substrate. The optical device further includes a first optical layer which is at least partially transmissive and at least partially reflective to incident light. The optical device further includes a second optical layer which is at least partially reflective to incident light. The second optical layer is spaced from the first optical layer. At least one of the first optical layer and the second optical layer is movable between a first position at a first distance from the first optical layer and a second position at a second distance from the first optical layer. Movement of the at least one of the first optical layer and the second optical layer between the first and second positions modulates the reflectivity of the device.

Claims

1. An inverse interferometric modulator display device, comprising:

a substrate;

a stationary reflector disposed on the substrate;

a deformable movable layer at least partially reflective to light and at least partially transmissive to light, the movable layer including an absorber layer, the movable layer spaced from the stationary reflector to form a cavity therebetween, wherein the movable layer is movable through the cavity between a relaxed position at a first distance from the stationary reflector and an actuated position at a second distance from the stationary reflector, the first distance being greater than the second distance such that when the movable layer is actuated it moves towards the stationary reflector,

wherein the device is configured to achieve a reflective colored state using interference when the movable layer is at the relaxed position at the first distance from the stationary reflector and achieve a dark state via absorption by the absorber layer when the movable layer is at the actuated position at the second distance from the stationary reflector.

2. The device of claim 1, wherein the absorber layer includes Chromium (Cr).

3. The device of claim 1, wherein the device further comprises a first electrode disposed over the substrate between the substrate and the movable layer, and wherein the movable layer includes a second electrode and the movable layer moves between the relaxed position and the actuated position in response to a voltage applied across the first and second electrodes.

4. The device of claim 3, further comprising a passivation layer disposed on the substrate between the first electrode and the substrate.

5. The device of claim 3, wherein at least one of the first electrode and the second electrode includes Indium Tin Oxide (ITO).

6. The device of claim 3, wherein the substrate includes a plastic, and wherein the first electrode includes the stationary reflector.

7. The device of claim 3, wherein the device further comprises a passivation layer disposed between the substrate and the first electrode.

8. The device of claim 3, further comprising a dielectric layer disposed between the first electrode and the movable layer.

9. The device of claim 1, wherein the substrate includes a metal.

10. The device of claim 1, wherein the substrate includes at least one of aluminum, steel, a metal foil, plastic, a ceramic material, and silicon.

11. The device of claim 1, wherein the stationary reflector includes a surface of the substrate on a side of the substrate proximate to the movable layer.

12. The device of claim 1, wherein the substrate is flexible.

13. The device of claim 1, wherein the substrate includes circuitry.

14. The device of claim 13, wherein the substrate is sufficiently non-transparent to shield the circuitry from light.

15. The device of claim 1, further comprising a dielectric layer disposed over the substrate between the substrate and the movable layer.

16. The device of claim 1, wherein the substrate has a thickness between about 0.1 millimeter and about 1.0 millimeter.

17. The device of claim 1, further comprising

a display including the substrate, the stationary reflector, and the deformable movable layer;

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

a memory device in electrical communication with the processor.

18. The device of claim 17, further comprising:

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

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

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

20. The device of claim 19, wherein the 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 the input data to the processor.

22. An inverse interferometric modulator display device comprising:

means for supporting;

a stationary means for reflecting light disposed on the supporting means;

a movable means at least partially reflective and partially transmissive to light, the movable means including an absorber layer and being deformable and spaced from the stationary light reflecting means to form a cavity therebetween, wherein the movable means is movable through the cavity between a relaxed position at a first distance from the stationary light reflecting means and an actuated position at a second distance from the stationary light reflecting means, the first distance being greater than the second distance such that when the movable layer is actuated it moves towards the stationary light reflecting means,

wherein the device is configured to reflect light of a certain color when the movable means is at the relaxed position at the first distance from the stationary light reflecting means and achieve a dark state via absorption by the absorber layer when the movable means is at the actuated position at the second distance from the stationary light reflecting means.

23. The device of claim 22, wherein the supporting means includes a substrate.

24. The device of claim 22, wherein the stationary light reflecting means includes a stationary reflector.

25. The device of claim 22, wherein the movable means includes a mechanical layer configured to be movable to the actuated and unactuated positions.

26. A method of manufacturing an inverse interferometric modulator display device comprising:

providing a substrate;

forming a stationary reflector on the substrate; and

forming a deformable movable layer over the stationary reflector, the movable layer including an absorber layer and at least partially reflective to light and at least partially transmissive to light, the movable layer spaced from the stationary reflector such that there is cavity formed therebetween, wherein the movable layer is configured to be movable through the cavity between a relaxed position at a first distance from the stationary reflector and an actuated position at a second distance from the stationary reflector, the first distance being greater than the second distance such that when the movable layer is actuated it moves towards the stationary reflector,

wherein the device is configured achieve a reflective colored state using interference when the movable layer is at the relaxed position at the first distance from the stationary reflector and achieve a dark state via absorption by the absorber layer when the movable layer is at the actuated position at the second distance from the stationary reflector.

27. The method of claim 26, further comprising:

forming a first electrode over the substrate between the substrate and the movable layer; and

forming a dielectric layer on the first electrode between the first electrode and the movable layer,

wherein forming the deformable movable layer includes forming a second electrode, wherein the device is configured such that the movable layer moves between the relaxed position and the actuated position in response to a voltage applied across the first and second electrodes.

28. The method of claim 26, wherein the substrate includes a metal.

29. The method of claim 26, further comprising forming a passivation layer between the substrate and the first electrode.

30. The method of claim 26, wherein the substrate includes plastic.

31. A method of modulating light, the method comprising:

providing an inverse interferometric display device comprising

a substrate;

a stationary reflector disposed on the substrate; and

a deformable movable layer including an absorber layer, the deformable movable layer at least partially reflective to light and at least partially transmissive to light, the movable layer spaced from the stationary reflector to form a cavity therebetween, wherein the movable layer is movable through the cavity between a relaxed position at a first distance from the stationary reflector and an actuated position at a second distance from the stationary reflector, the first distance being greater than the second distance such that when the movable layer is actuated it moves towards the stationary reflector,

wherein the device is configured to reflect light of a certain color when the movable layer is at the relaxed position at the first distance from the stationary reflector and achieve a dark state via absorption by the absorber layer when the movable layer is at the actuated position at the second distance from the stationary reflector; and

moving the deformable movable layer between the relaxed position at the first distance from the reflective layer and the actuated position at the second distance from the stationary reflector while the device has light incident thereon.

32. The method of claim 31, wherein the device further comprises a first electrode disposed over the substrate between the substrate and the movable layer, and wherein the movable layer includes a second electrode and the movable layer moves between the relaxed position and the actuated position in response to a voltage applied across the first and second electrodes.

33. The method of claim 32, wherein the device further comprises a passivation layer disposed between the first electrode and the substrate.

34. The method of claim 32, wherein the device further comprises a dielectric layer disposed on the first electrode between the first electrode and the movable layer.