Matching layer thin-films for an electromechanical systems reflective display device

• US 8,736,939 B2
• Filed: 11/04/2011
• Issued: 05/27/2014
• Est. Priority Date: 11/04/2011
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Hong, John Hyunchul, Ma, Jian J., Chang, Tallis Young, Lee, Chong Uk
• Primary Examiner(s): Spector, David N
• Application Number:
  US13/289,937
• Publication Number:
  US 20130114121A1
• Time in Patent Office: 935 Days
• Field of Search: 345/84, 345/85, 359/260, 359/290, 359/291, 359/292, 359/295, 359/578
• US Class Current: 359/260
• 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: G02B 26/08 for controlling the direction of light in light guides G02B6/35
• CPC Class Codes: G02B 5/285 comprising deposited thin solid films G02B5/281 - G02B5/289 take precedence; multilayered film filters for fibre optic multiplexing G02B6/29361

Abstract

This disclosure provides systems, methods and apparatus for an electromechanical systems reflective display device. In one aspect, an electromechanical systems display device includes a reflective layer and an absorber layer. The absorber layer is spaced apart from the reflective layer to define a cavity between the absorber layer and the reflective layer. The absorber layer is capable of transmitting light into the cavity, absorbing light, and reflecting light, and includes a metal layer. A plurality of matching layers are on a surface of the absorber layer facing away from the cavity, the plurality of matching layers including a first matching layer disposed on the absorber layer and a second matching layer disposed on the first matching layer.

Claims

1. An apparatus comprising:

a reflective layer;

an absorber layer spaced apart from the reflective layer to define a cavity between the absorber layer and the reflective layer, wherein the absorber layer is capable of transmitting light into the cavity, absorbing light, and reflecting light, the absorber layer including a metal layer;

a stack disposed on a surface of the reflective layer facing the cavity, the stack including a first dielectric layer and a second dielectric layer, the first dielectric layer including a low refractive index material and the second dielectric layer including a high index material; and

a plurality of matching layers on a surface of the absorber layer facing away from the cavity, the plurality of matching layers including a first matching layer disposed on the absorber layer and a second matching layer disposed on the first matching layer.

2. The apparatus of claim 1, the first matching layer having a first thickness, the second matching layer having a second thickness, the first and the second thicknesses configured to modify at least one of an amplitude and a phase of reflected light and transmitted light to alter a red-green-blue color saturation of the apparatus.

3. The apparatus of claim 1, wherein the first matching layer includes a first material having a first refractive index, wherein the second matching layer includes a second material having a second refractive index, and wherein the second refractive index is greater than the first refractive index.

4. The apparatus of claim 1, wherein the metal layer includes at least one of vanadium, chromium, tungsten, nickel, or an alloy of molybdenum-chromium.

5. The apparatus of claim 1, wherein the first matching layer includes at least one of silicon dioxide, magnesium fluoride, aluminum oxide, or a plastic.

6. The apparatus of claim 1, wherein the second matching layer includes at least one of silicon nitride, silicon oxynitride, titanium dioxide, zirconium dioxide, tantalum oxide, or antimony oxide.

7. The apparatus of claim 1, wherein the reflective layer is configured to be movable to vary a thickness of the cavity.

8. The apparatus of claim 1, wherein the plurality of matching layers further includes a third matching layer disposed on the second matching layer.

9. The apparatus of claim 1, further including a dielectric layer disposed on a surface of the absorber layer facing towards the cavity.

10. The apparatus of claim 1, further comprising:

a display;

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

a memory device that is configured to communicate with the processor.

11. The apparatus of claim 10, 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.

12. The apparatus of claim 10, 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, transceiver, and transmitter.

13. The apparatus of claim 10, further comprising:

an input device configured to receive input data and to communicate the input data to the processor.

14. An apparatus comprising:

a reflective layer;

an absorber layer spaced apart from the reflective layer to define a cavity between the absorber layer and the reflective layer, wherein the absorber layer is capable of transmitting light into the cavity, absorbing light, and reflecting light, the absorber layer including a metal layer;

a stack disposed on a surface of the reflective layer facing the cavity, the stack including a first dielectric layer and a second dielectric layer, the first dielectric layer including a low refractive index material and the second dielectric layer including a high index material;

a first matching layer having a first refractive index disposed on the absorber layer; and

a second matching layer having a second refractive index disposed on the first matching layer, the second refractive index being greater than the first refractive index.

15. The apparatus of claim 14, the first matching layer having a first thickness, the second matching layer having a second thickness, the first and the second thicknesses configured to modify at least one of an amplitude and a phase of reflected light and transmitted light to alter a red-green-blue color saturation of the apparatus.

16. The apparatus of claim 14, wherein the metal layer includes at least one of vanadium, chromium, tungsten, nickel, or an alloy of molybdenum-chromium.

17. The apparatus of claim 14, wherein the reflective layer is configured to be movable to vary a thickness of the cavity.

18. An apparatus comprising:

a reflective layer;

an absorber layer spaced apart from the reflective layer to define a cavity between the absorber layer and the reflective layer, wherein the absorber layer is capable of transmitting light into the cavity, absorbing light, and reflecting light, the absorber layer including a metal layer, wherein the reflective layer is configured to be movable to vary a thickness of the cavity;

a stack disposed on a surface of the reflective layer facing the cavity, the stack including a first dielectric layer and a second dielectric layer, the first dielectric layer including a low refractive index material and the second dielectric layer including a high index material; and

a plurality of matching layers on a surface of the absorber layer facing away from the cavity, the plurality of matching layers including a first matching layer disposed on the absorber layer and a second matching layer disposed on the first matching layer.

19. The apparatus of claim 18, the first matching layer having a first thickness, the second matching layer having a second thickness, the first and the second thicknesses configured to modify at least one of an amplitude and a phase of reflected light and transmitted light to alter a red-green-blue color saturation of the apparatus.

20. The apparatus of claim 18, wherein the metal layer includes at least one of vanadium, chromium, tungsten, nickel, or an alloy of molybdenum-chromium.

21. The apparatus of claim 18, wherein the first matching layer includes at least one of silicon dioxide, magnesium fluoride, aluminum oxide, or a plastic.

22. The apparatus of claim 18, wherein the second matching layer includes at least one of silicon nitride, silicon oxynitride, titanium dioxide, zirconium dioxide, tantalum oxide, or antimony oxide.

23. An apparatus comprising:

a reflective layer;

an absorber layer spaced apart from the reflective layer to define a cavity between the absorber layer and the reflective layer, wherein the absorber layer is capable of transmitting light into the cavity, absorbing light, and reflecting light, the absorber layer including a metal layer;

a stack proximate the reflective layer, the stack including means for reducing a spatial separation of standing wave first order nodes of different wavelengths of light; and

means for modifying at least one of an amplitude and a phase of reflected light and transmitted light to alter a red-green-blue color saturation of the apparatus.

24. The apparatus of claim 23, wherein the modifying means includes a plurality of matching layers on a surface of the absorber layer facing away from the cavity, the plurality of matching layers including a first matching layer disposed on the absorber layer and a second matching layer disposed on the first matching layer.

25. The apparatus of claim 23, wherein the stack includes a first dielectric layer and a second dielectric layer, the first dielectric layer including a low refractive index material and the second dielectric layer including a high index material.