Infrared and dual mode displays

• US 7,782,517 B2
• Filed: 06/21/2007
• Issued: 08/24/2010
• Est. Priority Date: 06/21/2007
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Sampsell, Jeffrey B., Griffiths, Jonathan Charles
• Primary Examiner(s): Sugarman; Scott J
• Assistant Examiner(s): PINKNEY, DAWAYNE
• Application Number:
  US11/766,725
• Publication Number:
  US 20080316568A1
• Time in Patent Office: 1,160 Days
• Field of Search: 359/237, 359/245, 359260-261, 359/263, 359/298, 359301-303
• US Class Current: 359/237
• 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 5/208 for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 3/3466 based on interferometric effect
• CPC Class Codes: H04N 2005/7466 Control circuits therefor

Abstract

One inventive aspect relates to a display comprising a display element configured to selectively reflect light of a first wavelength in the infrared range and light of a second wavelength in the visible spectrum. Another inventive aspect relates to a color display comprising at least three reflective display elements. Each display element is configured to selectively reflect light of a different wavelength in the visible range. At least one of the three reflective display element is further configured to selectively reflect light of a wavelength in the infrared range.

Claims

1. A display, comprising:

a display element comprising

a partially reflective fixed layer,

a reflective movable layer movable between an actuated position and an unactuated position, and

an optical resonant gap having a length defined between the fixed layer and the movable layer,

wherein the optical resonant gap length is configured to have, when the movable layer is in the unactuated position, a gap length that allows the display element to reflect light with a first order reflective response of a first wavelength in the infrared range and a second order reflective response of a second wavelength in the visible range.

2. The display of claim 1, wherein the display element forms a pixel.

3. The display of claim 1, wherein the display element forms an interferometric modulator.

4. The display of claim 1, wherein the first wavelength of the first order reflective response is within the range of approximately 800 to 1200 nm.

5. The display of claim 1, wherein the first wavelength of the first order reflective response is approximately 1900 nm.

6. The display of claim 1, wherein the display element is further configured to reflect light of a third and fourth wavelength in the visible range, and wherein reflecting light of a second, third, and fourth wavelength collectively and operatively displays light of an approximately white hue.

7. The display of claim 6, wherein the first wavelength is within the range of approximately 3 to 12 μ

m.

8. The display of claim 1, further comprising a filter located between the display element and a viewer, the filter being transparent to infrared light and opaque to visible light.

9. The display of claim 1, wherein the display is configured to work in a visible mode and an infrared mode, and the display is configured to be driven by a different driving scheme in each mode.

10. The display of claim 9, wherein the display configured to switch to the infrared mode when infrared illumination is detected.

11. The display of claim 9, further comprising an infrared detector configured to detect infrared illumination and send a signal to switch the display into the infrared mode when infrared illumination is detected.

12. The display of claim 11, wherein the infrared detector comprises a phototransistor or a photodiode.

13. The display of claim 1, further comprising:

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

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

14. The display of claim 13, further comprising a driver circuit configured to send at least one signal to the display elements.

15. The display of claim 14, further comprising a controller configured to send at least a portion of the image data to the driver circuit.

16. The display of claim 13, further comprising an image source module configured to send said image data to said processor.

17. The display of claim 16, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

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

19. A color display, comprising:

a pixel comprising at least three reflective display elements, each display element being configured to selectively reflect light of a different wavelength in the visible range, each display element comprising

a partially reflective fixed layer,

a reflective movable layer movable between an actuated position and an unactuated position, and

an optical resonant gap having a length defined between the fixed layer and the movable layer; and

wherein the gap length of at least one of the three reflective display elements is configured to have, when the movable layer is in the unactuated position, a gap length that reflects light with a first order reflective response of a first wavelength in the infrared range and a second order reflective response of a second wavelength in the visible range.

20. The display of claim 19, wherein each display element forms a subpixel.

21. The display of claim 19, wherein the three display elements form a pixel.

22. The display of claim 19, wherein each display element forms an interferometric modulator.

23. The display of claim 19, wherein each display element is configured to selectively reflect light of approximately a different one of the three primary colors:

red, blue, and green.

24. The display of claim 19, wherein at least two of the three reflective display element is further configured to selectively reflect light of a wavelength in the infrared range.

25. The display of claim 19, wherein the display is configured to work in a visible mode and an infrared mode, and the display is driven by a different driving scheme in each mode.

26. The display of claim 25, wherein the display is switched to the infrared mode when infrared illumination is detected.

27. The display of claim 25, wherein one or more of the three display elements which is not configured to reflect light of a wavelength in the infrared range is not driven by image data, while the display operates in infrared mode.

28. The display of claim 25, further comprising an infrared detector configured to detect infrared illumination and send a signal to switch the display into the infrared mode when infrared illumination is detected.

29. The display of claim 28, wherein the infrared detector comprises a phototransistor or a photodiode.

30. A display, comprising:

a display element comprising means for selectively reflecting light of a wavelength in the visible range and light of a wavelength in the infrared range, the selectively reflecting means comprising an optical resonant gap between a reflective movable layer and a partially reflective fixed layer, the optical resonant gap configured such that the display element has a first order reflective response of a first wavelength in the infrared range when the movable layer is in an unactuated position, and to have second order reflective response of a second wavelength in the visible range; and

means for sending at least one signal to the reflecting means.

31. The display of claim 30, wherein the reflecting means comprises an interferometric modulator.

32. The display of claim 30, wherein the sending means comprises a driver circuit.

33. The display of claim 30, further comprising means for blocking or absorbing light outside the infrared range.

34. The display of claim 33, wherein the blocking means comprises a light filter.

35. The display of claim 30, wherein the display is configured to work in a visible mode and an infrared mode, and the display is driven by a different driving scheme in each mode.

36. The display of claim 35, further comprising means for detecting infrared illumination.

37. The display of claim 36, wherein the display is configured to switch to the infrared mode when the detecting means detects infrared illumination.

38. The display of claim 36, wherein the detecting means comprises a phototransistor or a photodiode.

39. A method of operating a display, comprising:

driving a display with a drive scheme associated with a visible spectrum mode, the display including a display element having an optical resonant gap between a partially reflective movable layer and a partially reflective fixed layer, the optical resonant gap being configured to have, when the movable layer is in an unactuated position, a gap length that allows the display element to reflect light with a first order reflective response of a first wavelength in the infrared range and a second order reflective response of a second wavelength in the visible range;

receiving a signal to switch the display driving mode from a visible mode to an infrared mode;

switching the display from a visible mode to an infrared mode; and

driving the display with a scheme associated with the infrared mode.

40. The method of claim 39, wherein the display is configured to provide an infrared image in the infrared mode by interferometrically modulating received infrared illumination.

41. The method of claim 39, wherein the display is switched to the infrared mode in response to a signal received from a user request to switch to the infrared mode.

42. The method of claim 39, further comprising detecting infrared illumination, and sending a signal to switch the display driving mode in response to the detecting infrared illumination.

43. A display, comprising:

a first display element configured to selectively reflect light of a first range of wavelengths and a second range of wavelengths, wherein each of the first and second ranges are within one of the ultraviolet, visible, or infrared spectrums, the first display element comprising

a partially reflective fixed layer,

a reflective movable layer movable between an actuated position and an unactuated position, and

an optical resonant gap having a length defined between the fixed layer and the movable layer; and

wherein the optical resonant gap length is configured to have, when the movable layer is in the unactuated position, a gap length that allows the display element to reflect light with a first order reflective response of a first wavelength within one of the ultraviolet, visible, or infrared spectrums, and a second order reflective response of a second wavelength within another of the ultraviolet, visible, or infrared spectrums.

44. The display of claim 43, wherein the first range is within the ultraviolet spectrum and the second range is within either the visible or infrared spectrums.

45. The display of claim 43, wherein the first range is within the visible spectrum and the second rangy is within either the ultraviolet or infrared spectrums.

46. The display of claim 43, further comprising a second display element configured to selectively reflect light of a third range of wavelengths and a fourth range of wavelengths, wherein the first and third range are within the visible spectrums, and the second and fourth range are within the ultraviolet and infrared spectrums respectively.