METHOD AND DEVICE FOR MULTISTATE INTERFEROMETRIC LIGHT MODULATION

• US 20120139976A1
• Filed: 02/16/2012
• Published: 06/07/2012
• 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, CUMMINGS, WILLIAM J., GALLY, BRIAN J.
• Granted Patent: US 8,970,939 B2
• Time in Patent Office: Days
• US Class Current: 345/690
• 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
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A multi-state light modulator comprises a first reflector. A first electrode is positioned at a distance from the first reflector. A second reflector is positioned between the first reflector and the first electrode. The second reflector is movable between an undriven position, a first driven position, and a second driven position, each having a corresponding distance from the first reflector. In one embodiment, the three positions correspond to reflecting white light, being non-reflective, and reflecting a selected color of light. Another embodiment is a method of making the light modulator. Another embodiment is a display including the light modulator.

Claims

1. A display device comprising:

a first display element configured to be selectively switched among at least a first state having a first spectral reflectance being a first color, a second state having a second spectral reflectance being a second color different than the first color, and a third state having a third spectral reflectance being a black state.

2. The display device of claim 1, wherein the first color is substantially yellow and the second color is substantially blue, or wherein the first color is substantially yellow and the second color is substantially cyan.

3. The display device of claim 1, wherein the display element includes an interference-based display element.

4. The display device of claim 1, wherein the display element includes:

a first reflective layer; and

a second reflective layer movable with respect to the first reflective layer,

wherein the first state includes the second reflective layer in a first actuated position away from the first reflective layer,

wherein the second state includes the second reflective layer in a relaxed position, and

wherein the third state includes the second reflective layer in a second actuated position proximate to the first reflective layer, the relaxed position between the first actuated position and the second actuated position.

5. The display device of claim 4, wherein the display element includes:

a first actuation electrode, wherein the second reflective layer is movable to the first actuated position upon application of a voltage difference between the second reflective layer and the first actuation electrode, and

a second actuation electrode, wherein the second reflective layer is movable to the second actuated position upon application of a voltage difference between the second reflective layer and the second actuation electrode.

6. The display device of claim 5, wherein the first reflective layer is in electrical communication with the second actuation electrode.

7. The display device of claim 1, wherein the first color has an order and the second color has a same or higher order.

8. The display device of claim 1, further comprising:

a second display element configured to be selectively switched among at least a first state having a fourth spectral reflectance being a third color different than the first color and the second color, a second state having a fifth spectral reflectance being a fourth color different than the first color, the second color, and the third color, and a third state having a sixth spectral reflectance being a black state.

9. The display device of claim 8, wherein the first color is a first primary color, the second color is a second primary color, the fourth color is a third primary color, and the fifth color is a fourth primary color.

10. The display device of claim 8, wherein the third color is substantially yellow and the fourth color is substantially blue, or wherein the third color is substantially yellow and the fourth color is substantially cyan.

11. The display device of claim 8, wherein the third color has an order and the fourth color has a same or higher order.

12. The display device of claim 11, wherein the first color has an order and the second color has a same or higher order.

13. The display device of claim 1, further comprising:

a display including the first display element;

a processor configured to communicate with the display, the processor being configured to process image data; and

a memory device configured to communicate with the processor.

14. The display device of claim 13, further comprising:

a driver circuit configured to send at least one signal to the display; and

a controller configured to send at least a portion of the image data to the driver circuit.

15. The display device of claim 13, further comprising an image source module configured to send the image data to the processor, wherein the image source module includes at least one of a receiver, a transceiver, and a transmitter.

16. The display device of claim 13, further comprising an input device configured to receive input data and to communicate the input data to the processor.

17. A display device comprising:

first means for

reflecting a first color,

reflecting a second color different than the first color, and

reflecting a substantially black color; and

second means for

reflecting a third color different than the first color and the second color,

reflecting a fourth color different than the first color, the second color, and the third color, and

reflecting a substantially black color.

18. The display device of claim 17, wherein the first reflecting means and the second reflecting means both include an intereference-based display element configured to be selectively switched among at least a first state, a second state, and a third state.

19. The display device of claim 17, wherein at least one of the first reflecting means and the second reflecting means includes:

a first reflective layer; and

a second reflective layer movable between a first actuated position away from the first reflective layer, a second actuated position proximate to the first reflective layer, and a relaxed position between the first actuated position and the second actuated position.

20. The display device of claim 19, wherein the at least one of the first reflecting means and the second reflecting means further includes:

a first actuation electrode, wherein the second reflective layer is movable to the first actuated position upon application of a voltage difference between the second reflective layer and the first actuation electrode, and

a second actuation electrode, wherein the second reflective layer is movable to the second actuated position upon application of a voltage difference between the second reflective layer and the second actuation electrode.

21. The display device of claim 17, wherein the first color is a first primary color, the second color is a second primary color, the third color is a third primary color, and the fourth color is a fourth primary color.

22. The display device of claim 17, wherein the first color is substantially yellow and the second color is substantially blue, or wherein the first color is substantially yellow and the second color is substantially cyan, or wherein the third color is substantially yellow and the fourth color is substantially blue, or wherein the third color is substantially yellow and the fourth color is substantially cyan.

23. The display device of claim 17, wherein the first color has an order and the second color has a same or higher order, or wherein the third color has an order and the fourth color has a same or higher order, or wherein the first color has an order and the second color has a same or higher order and wherein the third color has an order and the fourth color has a same or higher order.

24. A method of generating an image, the method comprising:

selectively switching a first display element between at least a first state having a first spectral reflectance being a first color, a second state having a second spectral reflectance being a second color different than the first color, and a third state having a third spectral reflectance being a black state; and

selectively switching a second display element between at least a first state having a fourth spectral reflectance being a third color different than the first color and the second color, a second state having a fifth spectral reflectance being a fourth color different than the first color, the second color, and the third color, and a third state having a sixth spectral reflectance being a black state.

25. The method of claim 24, wherein the first color is a first primary color, the second color is a second primary color, the third color is a third primary color, and the fourth color is a fourth primary color.

26. The method of claim 24, wherein the first color is substantially yellow and the second color is substantially blue, or wherein the first color is substantially yellow and the second color is substantially cyan.

27. The method of claim 24, wherein the display element includes an interference-based display element.

28. The method of claim 24, wherein at least one of the first display element and second display element includes:

a first reflective layer; and

a second reflective layer movable with respect to the first reflective layer,

wherein the first state includes the second reflective layer in a first actuated position away from the first reflective layer,

wherein the second state includes the second reflective layer in a relaxed position, and

wherein the third state includes the second reflective layer in a second actuated position proximate to the first reflective layer, the relaxed position between the first actuated position and the second actuated position.

29. The method of claim 28, wherein the at least one of the first display element and the second display element includes:

a first actuation electrode, wherein the second reflective layer is movable to the first actuated position upon application of a voltage difference between the second reflective layer and the first actuation electrode, and

a second actuation electrode, wherein the second reflective layer is movable to the second actuated position upon application of a voltage difference between the second reflective layer and the second actuation electrode.

30. The method of claim 24, wherein the first color has an order and the second color has a same or higher order, or wherein the third color has an order and the fourth color has a same or higher order, or wherein the first color has an order and the second color has a same or higher order and the third color has an order and the fourth color has a same or higher order.