Resonant microcavity display

• US 5,616,986 A
• Filed: 08/18/1995
• Issued: 04/01/1997
• Est. Priority Date: 07/20/1993
• Status: Expired due to Fees

• Current Assignee: Quantum Vision
• Original Assignee: The University of Georgia Research Foundation, Inc.
• Inventors: Jacobsen, Stuart M., Jones, Michieal L., Jaffe, Steven M., Eilers, Hergen
• Primary Examiner(s): O'Shea, Sandra L.
• Assistant Examiner(s): Patel, Vip
• Application Number:
  US08/516,944
• Time in Patent Office: 592 Days
• Field of Search: 313/461, 313/466, 313/474, 313/506, 313/509, 372/92
• US Class Current: 313/461
• CPC Class Codes: H01J 29/28 with protective, conductive or reflective layers
• CPC Class Codes: H01J 61/42 by transforming the wavelength of the light by luminescence
• CPC Class Codes: H01J 63/06 Lamps with luminescent screen excited by the ray or stream
• CPC Class Codes: H05B 33/12 Light sources with substantially two-dimensional radiating surfaces
• CPC Class Codes: H05B 33/22 characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers

Abstract

A resonant microcavity display, comprising a thin-film resonant microcavity with a phosphor active region is disclosed. The microcavity comprises: a rigid substrate; a front reflector disposed upon the rigid substrate; a phosphor active region disposed upon the front reflector; and a back reflector disposed upon the active region. The display preferentially emits light that propagates along the axis perpendicular to plane of the display, due to its quantum mechanical properties. It exhibits high external efficiency, highly controllable chromaticity, high resolution, highly directional output and highly efficient heat transfer characteristics. For these reasons it provides a suitable display element for projection screen television, high definition television, direct view television, flat panel displays, optical coupling, and other applications.

Claims

1. A device comprising:

a cavity with an active region;

said active region including a material capable of having spontaneous light emission; and

said device capable of controlling the spontaneous light emission from said active region.

2. The device of claim 1 wherein:

said device can control at least one of;

(a) the amount of the light emitted from the active region;

(b) the angular spread of the light emitted from the active region; and

(c) the color of the light emitted from the active region.

3. The device of claim 1 wherein:

said material of said active region generates spontaneous light emission by the electronic transition of a localized center.

4. The device of claim 3 wherein:

said localized centers are luminescence centers.

5. The device of claim 3 wherein:

said localized center is an ion.

6. The device of claim 1 wherein:

said active region can generate light in a human visible range.

7. The device of claim 1 wherein:

said active region can generate light in a range that is outside of a human visible range.

8. The device of claim 1 comprising:

said device is a luminescent display.

9. The device of claim 1 wherein:

said device can generate incoherent light.

10. The device of claim 1 wherein:

said cavity is a resonant microcavity.

11. The device of claim 1 wherein:

said material is a phosphor.

12. The device of claim 1 wherein:

said cavity includes a first reflector and a second reflector, which first reflector is positioned opposite to said second reflector with said material of said active region located between said first reflector and said second reflector.

13. The device of claim 12 wherein:

said reflectors are asymmetric.

14. The device of claim 1 wherein:

said material of said active region is selected from the group which can be excited by at least one of (1) bombardment by externally generated electrons, (2) by an electric field, and (3) by using photons.

15. The device of claim 1 wherein:

said material of said active region is selected from the group of materials which can be excited in order to generate at least one of (1) cathodoluminescence, (2) electroluminescence, and (3) photoluminescence.

16. The device of claim 1 wherein:

said device is a structure that can modify spontaneous light emission of the material contained in the active region.

17. The device of claim 1 including:

a second cavity located relative to said cavity.

18. The device of claim 17 wherein said second cavity is a reflector.

19. The device of claim 1 including:

a plurality of cavities located relative to said cavity.

20. The device of claim 19 wherein:

said at least one of said plurality of cavities is a reflector.

21. The device of claim 1 wherein:

said device is a light source.

22. The device of claim 1 wherein:

said device includes a structure that can control at least one of (1) decay rates, (2) directional characteristics, or (3) frequency characteristics of said material in order to control the spontaneous light emission.

23. The device of claim 1 wherein:

said cavity is a optical resonant cavity.

24. The device of claim 1 comprising:

said material of said active region has spontaneous light emission governed by the intrinsic properties of said material.

25. The device of claim 1 wherein:

said active region includes a phosphor material.

26. The device of claim 1 comprising:

said material of said active region has spontaneous light emission resulting from the bulk characteristics of the material.

29. The device of claim 1 wherein:

said material in said cavity having an emission spectrum which is different from the natural emission spectrum of the material outside of the cavity.

30. The device of claim 29 wherein:

said cavity has a dimension; and

said dimension is chosen in accordance with a desire emission spectrum of the cavity.

31. The device of claim 1 wherein:

said material of said active region decays in order to emit light;

said device capable of controlling the spontaneous light emission of said active region by controlling the decay of said material.

32. The device of claim 1 wherein:

said active region includes two or more materials.

33. The device of claim 1 wherein:

said active region includes two or more materials, each a different phosphor.

34. The device of claim 1 wherein:

said cavity includes two or more active regions.

27. The device of class 1 wherein:

said active region is designed to promote the formation of standing waves for emitting light.

28. The device of class 1 comprising:

said material of said active region has a luminous efficiency of about at least one percent, where luminous efficiency is defined as the ratio of light output over power input.

35. A method of producing a luminescent display which comprises:

growing a resonant microcavity including a phosphor active region for said microcavity.

36. The method of claim 35 including:

growing said phosphor active region inside of said microcavity.

37. The method of claim 35 wherein said microcavity has a first reflector and a second reflector, the method including:

growing said phosphor active region between said first reflector and said second reflector.

38. A device comprising:

a resonant microcavity with an active region; and

said active region having a material disposed therein that absorbs light and generates an electrical signal.

39. A memory storage device comprising:

a resonant microcavity with an active region;

said active region having a material which has a decay rate; and

said resonant microcavity being tunable in order to effect the lifetime of the material in order to store information.

40. The device of claim 39 wherein:

said material is an optical material.

41. A memory storage device comprising:

a resonant microcavity with an active region; and

said active region having a material with can absorb energy in order to burn holes in the material to store information.

42. The device of claim 41 wherein:

said material is an optical material.

43. A light valve comprising:

a first resonant microcavity;

a second resonant microcavity, said second microcavity having an active region with a material that is characterized in that light is generated by spontaneous emissions; and

said first resonant microcavity being tunable in order to modulate the intensity of light emitted from said second resonant microcavity.

44. A device comprising:

a resonant microcavity with an active region; and

said active region having a phosphor disposed therein for spontaneously emitting light.

45. The device of claim 44 comprising:

a luminescent display.

46. The device of claim 44 wherein:

said resonant microcavity is a thin-film resonant microcavity.

47. The device of claim 44 wherein:

said device is capable of controlling the spontaneous light emission of said phosphor.

48. A device comprising:

one or more cavities;

at least one of said one or more cavities having an active region which is capable of having spontaneous light emission; and

said device capable of controlling spontaneous light emission from said active region.

49. The device of claim 48 comprising:

each of a plurality of said cavities having an active region; and

said device capable of controlling spontaneous light emission from said active regions.