Micromirror array lens with optical surface profiles

• US 7,619,807 B2
• Filed: 10/31/2007
• Issued: 11/17/2009
• Est. Priority Date: 11/08/2004
• Status: Active Grant

• Current Assignee: Stereo D Inc., Stereo Display, Inc.
• Original Assignee: Angstrom, Inc., Stereo Display, Inc.
• Inventors: Seo, Cheong Soo, Cho, Gyoung Il, Baek, Sang Hyune, Sohn, Jin Young
• Primary Examiner(s): Choi; William C
• Application Number:
  US11/933,105
• Publication Number:
  US 20080049291A1
• Time in Patent Office: 748 Days
• Field of Search: 359/290, 359/291, 359/726, 359/727, 359/846
• US Class Current: 359/290
• CPC Class Codes: G02B 17/002 Arrays of reflective systems
• 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 5/10 with curved faces
• CPC Class Codes: G02B 5/188 Plurality of such optical elements formed in or on a supporting substrate
• CPC Class Codes: G02B 5/1895 such optical elements having dioptric power

Abstract

A Micromirror Array Lens comprises a plurality of micromirrors arranged on a flat or a curved surface to reflect incident light. Each micromirror in the Micromirror Array Lens is configured to have at least one motion. The Micromirror Array Lens forms at least one optical surface profile reproducing free surfaces by using the motions of the micromirrors. The free surface can be any two or three-dimensional continuous or discrete reflective surface. The Micromirror Array Lens having the corresponding optical surface profile provides optical focusing properties substantially identical to those of the free surface. The Micromirror Array Lens can forms various optical elements such as a variable focal length lens, a fixed focal length lens, an array of optical switches, a beam steerer, a zone plate, a shutter, an iris, a multiple focal length lens, other multi-function optical elements, and so on.

Claims

1. A Micromirror Array Lens comprising a plurality of micromirrors, wherein each of the micromirrors has a reflective surface and is configured to have at least one motion to form at least one optical surface profile, wherein each optical surface profile satisfies a same phase condition and a converging condition.

2. The Micromirror Array Lens of claim 1, wherein each optical surface profile reproduces an optical lens with predetermined optical properties.

3. The Micromirror Array Lens of claim 2, wherein the optical surface profile is determined by rotation and translation of the micromirrors in the Micromirror Array Lens.

4. The Micromirror Array Lens of claim 2, wherein the optical property is a focal length of the Micromirror Array Lens.

5. The Micromirror Array Lens of claim 2, wherein the optical property is an optical axis of the Micromirror Array Lens.

6. The Micromirror Array Lens of claim 2, wherein the optical property is a field of view of the Micromirror Array Lens.

7. The Micromirror Array Lens of claim 2, wherein the optical property is an aberration correction of the Micromirror Array Lens.

8. The Micromirror Array Lens of claim 2, wherein the optical property is an optical power of the Micromirror Array Lens.

9. The Micromirror Array Lens of claim 2, wherein the optical property is an optical magnification of the Micromirror Array Lens.

10. The Micromirror Array Lens of claim 2, wherein the optical property is an optical aperture of the Micromirror Array Lens.

11. The Micromirror Array Lens of claim 1, wherein the Micromirror Array Lens has a plurality of optical surface profiles.

12. The Micromirror Array Lens of claim 11, wherein the Micromirror Array Lens is configured to have variable optical properties by changing the optical surface profile of the Micromirror Array Lane by controlling the micromirrors.

13. The Micromirror Array Lens of claim 12, wherein the Micromirror Array Lens is configured to have a variable focal length, wherein the focal length of the Micromirror Array Lens is varied by changing the optical surface profile of the Micromirror Array Lens by controlling the micromirrors.

14. The Micromirror Array Lens of claim 12, wherein the Micromirror Array Lens is configured to have a variable optical axis, wherein the optical axis of the Micromirror Array Lens is varied by changing the optical surface profile of the Micromirror Array Lens by controlling the micromirrors.

15. The Micromirror Array Lens of claim 12, wherein the Micromirror Array Lens is configured to have a variable aperture size, wherein the aperture size of the Micromirror Array Lens is varied by changing the optical surface profile of the Micromirror Array Lens by controlling the micromirrors.

16. The Micromirror Array Lens of claim 12, wherein the Micromirror Array Lens is configured to have a variable field of view, wherein the field of view of the Micromirror Array Lens is varied by changing the optical surface profile of the Micromirror Array Lens by controlling the micromirrors.

17. The Micromirror Array Lens of claim 12, wherein the Micromirror Array Lens is configured to have a variable aberration correction, wherein the aberration correction of the Micromirror Array Lens is varied by changing the optical surface profile of the Micromirror Array Lens by controlling the micromirrors.

18. The Micromirror Array Lens of claim 12, wherein the Micromirror Array Lens is configured to have a variable optical power, wherein the optical power of the Micromirror Array Lens is varied by changing the optical surface profile of the Micromirror Array Lens by controlling the micromirrors.

19. The Micromirror Array Lens of claim 12, wherein the Micromirror Array Lens is configured to have a variable optical magnification, wherein the optical magnification of the Micromirror Array Lens is varied by changing the optical surface profile of the Micromirror Array Lens by controlling the micromirrors.

20. The Micromirror Array Lens of claim 1, wherein the optical surface profile is formed to reproduce a free surface having its characteristic optical property selected from the group of focal length, optical axis, field of view, aberration correction, optical power, optical magnification, and aperture size of the Micromirror Array Lens.

21. The Micromirror Array Lane of claim 20, wherein the Micromirror Array Lens is configured to provide an adjustable aperture having a plurality of aperture sizes by controlling micromirrors, wherein the adjustable aperture controls the amount of incident light admitted to an image sensor by changing the aperture size.

22. The Micromirror Array Lens of claim 20, wherein the Micromirror Array Lens is configured to focus light and steer the focused light across an area of interest by changing the optical surface profiles of the Micromirror Array Lens.

23. The Micromirror Array Lens of claim 20, wherein the Micromirror Array Lens is configured to have optical shutter function wherein at least one of the optical surface profile of the Micromirror Array Lens makes incident light redirected out of an image sensor when the optical shutter function is on.

24. The Micromirror Array Lens of claim 20, wherein the Micromirror Array Lens is configured to control amount of incident light admitted to an image sensor by adjusting the aperture size of the Micromirror Array Lens.

25. The Micromirror Array Lens of claim 1, wherein the Micromirror Array Lens comprises a control circuitry configured to control the micromirrors, wherein the control circuitry is constructed under the micromirrors by using microelectronics fabrication technologies.

26. The Micromirror Array Lens of claim 25, wherein the micromirrors in the Micromirror Array Lens are controlled by a common input signal to the control circuitry to form an optical surface profile and change the optical surface profile of the Micromirror Array Lens.

27. The Micromirror Array Lens of claim 26, wherein the optical surface profile of the Micromirror Array Lens is changed discretely by controlling the micromirrors in the Micromirror Array Lens with discrete motions.

28. The Micromirror Array Lens of claim 1, wherein the optical surface profile reproduces a portion of surface of revolution of a conic section.

29. The Micromirror Array Lens of claim 1, wherein the optical surface profile reproduces an aspheric surface.

30. The Micromirror Array Lens of claim 1, wherein the optical surface profile reproduces an anamorphic surface.

31. The Micromirror Array Lens of claim 1, wherein the optical surface profile reproduces a free surface.

32. The Micromirror Array Lens of claim 1, wherein the optical surface profile reproduce a Fresnel type reflective surface.

33. The Micromirror Array Lens of claim 1, wherein the optical surface profile reproduces a diffractive optical element surface.

34. The Micromirror Array Lens of claim 1, wherein the micromirrors in the Micromirror Array Lens is arranged in a flat surface.

35. The Micromirror Array Lens of claim 1, wherein the micromirrors in the Micromirror Array Lens is arranged in a surface with a predetermined curvature.

36. The Micromirror Array Lens of claim 1, wherein the micromirrors in the Micromirror Array Lens have a substantially flat surface.

37. The Micromirror Array Lens of claim 1, wherein the micromirrors in the Micromirror Array Lens have a surface with a predetermined curvature.

38. The Micromirror Array Lens of claim 1, wherein the micromirrors in the Micromirror Array Lens have a curved surface with a variable curvature.

39. The Micromirror Array Lens of claim 1, wherein the micromirrors in the Micromirror Array Lens have a shape selected from the group consisting of a fan shape, a hexagonal shape, a rectangular shape, a square shape, a triangle shape and a circular shape.

40. The Micromirror Array Lens of claim 1, wherein the reflective surface of the micromirrors is made of the material selected from the group consisting of metal, metal coated with multi-layer dielectric material, metal coated with antioxidant, and multi-layer dielectric material.

41. The Micromirror Array Lens of claim 40, wherein the metal of the reflective surface is made of material selected from the group consisting of silver (Ag), aluminum (Al), gold (Au), nickel (Ni.), chromium (Cr), and platinum (Pt) to have high reflectivity.

42. The Micromirror Array Lens of claim 40, wherein the metal of the reflective surface is protected by a coating layer deposited on the reflective surface with material selected from the group consisting of silicon oxide (SiO₂), aluminum oxide (Al₂O₃), magnesium oxide (MgO), titanium oxide (TiO₂), cesium oxide (CeO₂), silicon nitride (Si₃N₄), titanium nitride (TiN), magnesium fluoride (MgF₂), zinc sulfide (ZnS), zinc selenide (ZnSe), polycarbonate, polyester, polyethylene naphthalate, and fluoropolymer.

43. The Micromirror Array Lens of claim 1, wherein the micromirrors in the Micromirror Array Lens comprise actuating components and mechanical structures configured to make the micromirrors have multiple degrees of freedom motion.

44. The Micromirror Array Lens of claim 43, wherein the actuating components are actuated by electrostatic force.

45. The Micromirror Array Lens of claim 43, wherein the actuating components are actuated by electromagnetic force.

46. The Micromirror Array Lens of claim 1, wherein each micromirror in the Micromirror Array Lens is configured to have an independent motion.

47. The Micromirror Array Lens of claim 1, wherein each micromirror in the Micromirror Array Lens is individually controlled to form an optical surface profile.

48. A Micromirror Array Lens comprising a plurality of micromirrors, wherein each of the micromirrors has a reflective surface and is configured to have a plurality of motions, wherein the Micromirror Array Lens is configured to form a plurality of optical surface profiles and harm at least one variable optical property, wherein the optical property can be a focal length, an optical axis, an aberration correction, an optical power, a field of view, an optical magnification, and an aperture size of the Micromirror Array Lens.

49. A Micromirror Array Lens comprising a plurality of micromirrors, wherein each of the micromirrors has a reflective surface, wherein the Micromirror Array Lens is configured to form an optical surface profile reproducing an arbitrary free surface, wherein the arbitrary free surface includes a spherical free surface, an aspherical free surface, a portion of surface of revolution of a conic section, a revolution symmetric free surface, a line symmetric free surface, an anamorphic surface, a continuous free surface, a discrete free surface, a Fresnel type reflective surface, and a diffractive optical element surface.