Interferometric modulation of radiation

• US 20020024711A1
• Filed: 10/10/2001
• Published: 02/28/2002
• Est. Priority Date: 05/05/1994
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Iridigm Display Corporation (Qualcomm, Inc.)
• Inventors: Miles, Mark W.
• Granted Patent: US 6,680,792 B2
• Time in Patent Office: Days
• US Class Current: 359/247
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G01J 3/26 using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters
• CPC Class Codes: G02B 2006/12104 Mirror; Reflectors or the like
• CPC Class Codes: G02B 2027/0112 comprising device for genereting colour display
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• 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 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 26/085 the reflecting means being moved or deformed by electromagnetic means
• CPC Class Codes: G02B 26/0858 the reflecting means being moved or deformed by piezoelectric means
• CPC Class Codes: G02B 27/01 Head-up displays
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 6/12 of the integrated circuit kind electric integrated circuits H01L27/00
• CPC Class Codes: G02F 1/13725 based on guest-host interaction G02F1/13762, G02F1/13737, take precedence
• CPC Class Codes: G02F 1/216 using liquid crystals, e.g. liquid crystal Fabry-Perot filters
• CPC Class Codes: G02F 2203/03 scattering
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 3/2074 using sub-pixels
• CPC Class Codes: G09G 3/3466 : based on interferometric effect

Abstract

An Interferometric Modulator (IMod) is a microelectromechanical device for modulating light using interference. The colors of these devices may be determined in a spatial fashion, and their inherent color shift may be compensated for using several optical compensation mechanisms. Brightness, addressing, and driving of IMods may be accomplished in a variety of ways with appropriate packaging, and peripheral electronics which can be attached and/or fabricated using one of many techniques. The devices may be used in both embedded and directly perceived applications, the latter providing multiple viewing modes as well as a multitude of product concepts ranging in size from microscopic to architectural in scope.

Claims

1. A modulator of light comprising

an interference cavity for causing interference modulation of the light, the cavity having a mirror, the mirror comprising a corrugated surface.

12. The structure of claim 1 wherein the brightness and/or color are controlled by error diffusion.

34. The device of claim 1 comprising an application incorporating aggregate arrays of IMods.

2. A modulator of light comprising

an interference cavity for causing interference modulation of the light to produce a color condition visible to an observer, the color condition being determined by the spatial configuration of the modulator.

3. The modulator of claim 2 wherein the interference cavity comprises

a mirror and

a supporting structure holding the mirror,

and wherein the spatial configuration comprises the configuration of the supporting structure.

4. The modulator of claim 2 wherein the interference cavity comprises

a mirror, and wherein

the spatial configuration comprises patterning of the mirror.

5. The modulator of claim 2 wherein the interference cavity comprises

a mirror, and

a supporting structure holding the mirror, and wherein the supporting structure is coupled to a rear surface of the mirror.

6. A structure for modulating light comprising

modulators of light each including an interference cavity for causing interference modulation of the light, each of the modulators having a viewing cone,

the viewing cones of different ones of the modulators being aligned in different directions.

7. The structure of claim 6 in which the viewing cones of the different modulators are aligned in random directions.

8. The structure of claim 6 in which the viewing cones of the modulators are narrower than the viewing cone of the overall structure.

9. A structure for modulating light comprising

modulators of light each including an interference cavity for causing interference modulation of the light, and

a liquid medium in which the modulators are suspended.

10. A structure for modulating light comprising

modulators of light each including an interference cavity for causing interference modulation of the light, and

an optical compensation mechanism coupled to the modulators which enhances the optical performance of the structure.

11. The structure of claim 10 in which the mechanism comprises a combination of one or more of a holographically patterned material, a photonic crystal array, a multilayer array of dielectric mirrors, or an array of microlenses.

14. The application of claim 13 wherein the IMod is used in the analysis of chemical, organic, or biological components.

18. The system of claim 17 in which the control electronics are configured to generate projected images for virtual environments.

19. The application of claim 18 in which the array includes liquid crystals or microelectromechanical modulators.

13. A modulator of light comprising

an interferometric modulator, and

an optical fiber coupled to the interferometric modulator.

15. An information printing system comprising

an array of interference modulators of light,

a lens system, and

a media transport mechanism.

16. An image capture system comprising

an array of interference modulators of light,

a lens system, and

a media transport mechanism.

17. An information projection system comprising

an array of interference modulators of light,

a lens system,

mechanical scanners, and

control electronics.

20. A product comprising

an operational element, a display element,

a housing enclosing the operational element and having a display element, the display element including a surface viewed by a user, and

an array of interference modulators of light on the surface.

21. The product of claim 20 in which the operational element comprises a personal communications device.

22. The product of claim 20 in which the operational element comprises a personal information tool.

23. The product of claim 20 in which the operational element comprises a vehicular control panel.

24. The product of claim 20 in which the operational element comprises an instrument control panel.

25. The product of claim 20 in which the operational element comprises a time keeping device.

26. The product of claim 20 in which the operational element comprises an article of clothing or portion thereof.

27. The product of claim 20 in which the operational element comprises an item of jewelry.

28. The product of claim 20 in which the operational element comprises a sporting good.

29. The product of claim 20 in which the array substantially alters the aesthetic or decorative features of the surface.

30. The product of claim 29 in which the aesthetic component responds to a state of use of the consumer product.

31. The product of claim 29 in which the aesthetic component is downloaded or derived from an external source.

32. The product of claim 29 wherein the array also provides information.

33. The application of claim 29 wherein liquid crystals, field emission, plasma, or organic emitter based technologies and associated electronics are used as the modulation array.

35. The application of claim 34 wherein the array is used to display information on signs or billboards.

36. A vehicle comprising

a body panel,

an array of interference modulators of light on a surface of the body panel, and

electronic circuitry for determining the aesthetic appearance of the body panel by controlling the array of interference modulators.

37. A building comprising

external surface elements,

an array of interference modulators of light on a surface of the body panel, and

electronic circuitry for determining the aesthetic appearance of the surface elements by controlling the array of interference modulators.

38. A full color active display comprising

a liquid crystal medium, and

interferometric elements embedded in the medium.

39. A structure comprising

a substrate,

micromechanical elements formed on the surface of the substrate, and

electronics connected to control the elements, the electronics being formed also on the surface of the substrate.