Apparatus and methods relating to wavelength conditioning of illumination

• US 20020135763A1
• Filed: 01/31/2002
• Published: 09/26/2002
• Est. Priority Date: 02/02/2001
• Status: Active Grant

• Current Assignee: Tidal Photonics Incorporated
• Original Assignee: Tidal Photonics Incorporated
• Inventors: Stange, Ulrich, MacKinnon, Nicholas B., MacAulay, Calum E.
• Granted Patent: US 6,781,691 B2
• Time in Patent Office: Days
• US Class Current: 356/326
• CPC Class Codes: A61N 5/0616 Skin treatment other than tanning
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent
• CPC Class Codes: F21S 10/02 changing colors F21S10/002 - F21S10/007, F21S10/04 take precedence
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: H05B 41/3922 and measurement of the incident light
• CPC Class Codes: H05B 47/155 Coordinated control of two or more light sources
• CPC Class Codes: H05B 47/165 following a pre-assigned programmed sequence; Logic control [LC]

Abstract

Lighting systems comprising a spectrum former upstream from a reflective pixelated spatial light modulator (reflective SLM), the SLM reflecting substantially all of the light in the spectrum into at least two different light paths, that do not reflect back to the light source or the spectrum former. At least one of the light paths acts as a projection light path and transmits desired light out of the lighting system. The lighting systems provide virtually any desired color(s) and intensity(s) of light, and avoid overheating problems by deflecting unwanted light and other electromagnetic radiation out of the system or to a heat management system. The systems can be part of another system, a luminaire, or any other suitable light source. The systems can provide virtually any desired light, from the light seen at the break of morning to specialized light for treating cancer or psoriasis, and may change color and intensity at speeds that are perceptually instantaneous.

Claims

1. A lighting system that provides a variable selected spectral output and a variable wavelength dependent intensity distribution, the lighting system comprising a light path that comprises:

a) a spectrum former able to provide a spectrum from a light beam traveling along the light path, and

b) a reflective pixelated spatial light modulator located downstream from and optically connected to the spectrum former, the reflective pixelated spatial light modulator reflecting substantially all light impinging on the reflective pixelated spatial light modulator and switchable between at least first and second reflected light paths that do not reflect back to the spectrum former,

wherein the reflective pixelated spatial light modulator is operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the reflective pixelated spatial light modulator to reflect a desired segment of light in the spectrum in first reflected light path and reflect other light in the spectrum in at least one other direction that is not back to the spectrum former, the desired segment of light consisting essentially of a desired selected spectral output and a desired wavelength dependent intensity distribution.

2. The lighting system of claim 1 wherein the system further comprises a light source located upstream from the spectrum former and the spectrum former comprises at least one of a prism and a diffraction grating.

3. The lighting system of claim 1 wherein the spectrum former comprises a variable wavelength optical filter.

4. The lighting system of claim 1 wherein the spectrum former comprises a mosaic optical filter.

5. The lighting system of claim 1 wherein the system does not comprise an optical element between the spectrum former and the reflective pixelated spatial light modulator that provides a substantially enhanced image of the spectrum from the spectrum former to the reflective pixelated spatial light modulator.

6. The lighting system of claim 1 wherein the system further comprises an optical element between the spectrum former and the reflective pixelated spatial light modulator that provides a substantially enhanced image of the spectrum from the spectrum former to the reflective pixelated spatial light modulator.

7. The lighting system of claim 1 wherein the reflective pixelated spatial light modulator is a first reflective pixelated spatial light modulator, and wherein the desired segment of light is directed to a second reflective spatial light modulator operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the second reflective pixelated spatial light modulator to reflect the desired segment of light in one direction and reflect other light in the spectrum in at least one other direction.

8. The lighting system of claim 7 wherein the first reflective pixelated spatial light modulator and the second reflective pixelated spatial light modulator are connected to a single controller.

9. The lighting system of claim 1 wherein the system further comprises an optical projection device located downstream from the first reflective pixelated spatial light modulator to project light out of the lighting system as a directed light beam.

10. The lighting system of claim 1 wherein the desired segment of light is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of at least one of a known lamp, a cathode ray tube image display device, a light emissive image display device, firelight, candlelight, and sunlight.

11. The lighting system of claim 1 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy corresponding to a desired natural ambient lighting scenario.

12. The lighting system of claim 1 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy for disease treatment.

13. The lighting system of claim 1 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy for photodynamic therapy.

14. The lighting system of claim 1 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy for disease diagnosis.

15. The lighting system of claim 1 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy that can enhance contrast for detection or discrimination of a desired object in a scene.

16. The lighting system of claim 1 wherein the reflective pixelated spatial light modulator is a digital micromirror device.

18. The lighting system of claim 17 wherein the system further comprises a light source located upstream from the spectrum former and the spectrum former comprises a prism or a diffraction grating.

19. The lighting system of claim 18 wherein the pixelated spatial light modulator is a first pixelated spatial light modulator, and wherein the desired segment of light is directed to a second pixelated spatial light modulator operably connected to at least one controller containing computer-implemented programming that controls the on/off pattern of pixels in the second pixelated spatial light modulator to reflect a desired segment of light in one direction and deflect other light in the spectrum in at least one other direction.

20. The lighting system of any one of claims 18 wherein the system further comprises an optical projection device located downstream from at least one of the first pixelated spatial light modulator and the second pixelated spatial light modulator to project light as a directed light beam.

17. A lighting system that provides a variable selected spectral output and wavelength dependent intensity distribution, the lighting system comprising a light path that comprises:

a) a spectrum former able to provide a spectrum from a light beam traveling along the light path, and

b) a pixelated spatial light modulator located downstream from and optically connected to the spectrum former,

wherein the pixelated spatial light modulator is operably connected to at least one controller containing computer-implemented programming that controls the on/off pattern of pixels in the pixelated spatial light modulator to reflect a desired segment of light in the spectrum in one direction and reflect other light in the spectrum in at least one other direction, the desired segment of light consisting essentially of a desired selected spectral output and a desired wavelength dependent intensity distribution, and wherein the system does not comprise an optical element between the spectrum former and the pixelated spatial light modulator that provides an enhanced image of the spectrum from the spectrum former to the pixelated spatial light modulator.

21. A stand alone luminaire sized to project light onto a scene and having a variable selected spectral output and wavelength dependent intensity distribution, the luminaire comprising:

a) a high output light source,

b) a spectrum former optically connected to and downstream from the light source to provide a spectrum from a light beam emitted from the light source,

c) an optical element connected to and downstream from the spectrum former that provides an enhanced image of the spectrum;

d) a reflective pixelated spatial light modulator located downstream from and optically connected to the spectrum former, the reflective pixelated spatial light modulator reflecting substantially all light impinging on the reflective pixelated spatial light modulator and switchable between at least first and second reflected light paths that do not reflect back to the spectrum former, wherein the reflective pixelated spatial light modulator is operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the reflective pixelated spatial light modulator to reflect a desired segment of light in the spectrum in first reflected light path and reflect other light in the spectrum in at least one other direction that is not back to the spectrum former, the desired segment of light consisting essentially of a desired selected spectral output and a desired wavelength dependent intensity distribution; and

,

e) a projection system optically connected to and downstream from the pixelated spatial light modulator in the first direction, wherein the projection system projects the desired segment as a directed light beam to illuminate the scene.

22. The luminaire of claim 21 wherein the luminaire further comprises a detector optically connected to and downstream from the pixelated spatial light modulator, the detector also operably connected to a controller containing computer-implemented programming able to determine from the detector whether the desired segment contains a desired selected spectral output and a desired wavelength dependent intensity distribution, and adjust the on/off pattern of pixels in the pixelated spatial light modulator to improve the correspondence between the desired segment and the desired selected spectral output and the desired wavelength dependent intensity distribution.

23. The luminaire of claim 21 or 22 wherein the luminaire further comprises a heat removal element operably connected to the light source to remove undesired energy emitted from the light source toward at least one of the reflective pixelated spatial light modulator, the optical element, and the spectrum former.

24. The luminaire of claim 21 wherein the reflective pixelated spatial light modulator is a digital micromirror device.

25. The luminaire of claim 21 wherein the pixelated spatial light modulator is a first pixelated spatial light modulator, and wherein the desired segment of light is directed to a second spatial light modulator operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the second pixelated spatial light modulator to provide an improved desired selected spectral output and desired wavelength dependent intensity distribution in the desired segment of light.

26. The luminaire of claim 23 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired portion of a wavelength dependent distribution of output energy of at least one of a known lamp, a cathode ray tube image display device, a light emissive image display device and a source of optical radiation.

27. The luminaire of claim 23 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy corresponding to a desired natural ambient lighting scenario.

28. The luminaire of claim 23 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy for disease treatment.

29. The luminaire of claim 23 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy for photodynamic therapy.

30. The luminaire of claim 23 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy for disease diagnosis.

31. The luminaire of claim 23 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy that can enhance contrast for detection or discrimination of a desired object in a scene.

32. The luminaire of claim 23 wherein the heat removal element is located between the lamp and the first spatial light modulator.

33. The luminaire of claim 23 wherein the heat removal element is located between the lamp and the spectrum former.

34. The luminaire of claim 23 wherein the heat removal element comprises a dichroic mirror.

35. The luminaire of claim 23 wherein the heat removal element comprises a dichroic mirror that transmits desired wavelengths and reflects undesired wavelengths.

36. The luminaire of claim 23 wherein the heat removal element comprises a dichroic mirror that reflects desired wavelengths and transmits undesired wavelengths.

37. The luminaire of claim 23 wherein the undesired energy is directed to an energy absorbing surface and thermally conducted to a radiator.

38. The luminaire of claim 21 wherein the system further comprises a spectral recombiner optically connected to and located downstream from the pixelated spatial light modulator.

39. The luminaire of claim 38 wherein the spectral recombiner comprises a directional light diffuser.

40. The luminaire of claim 38 wherein the spectral recombiner comprises a holographic optical diffusing element.

41. The luminaire of claim 38 wherein the spectral recombiner comprises an operable combination of a light pipe and at least one of a lenslet array and a holographic optical diffusing element.

42. The luminaire of claim 22 wherein the detector is located in the at least one other direction.

43. The luminaire of claim 42 wherein the detector comprises at least one of a CCD, a CID, a CMOS, and photodiode array.

44. The luminaire of claim 23 wherein the high output light source, the spectrum former, the optical element that provides an enhanced image, the pixelated spatial light modulator, and the projection system, are all located in a single housing.

46. The method of claim 45 wherein the method further comprises emitting the light beam from a light source located in a same housing as and upstream from the spectrum former, and wherein the spectrum former comprises at least one of a prism and a diffraction grating.

47. The method of claim 45 or 46 wherein the method further comprises switching the modified light beam between the first reflected light path and the second reflected light path.

48. The method of claim 47 wherein the method further comprises passing the light beam by an optical element between the spectrum former and the reflective pixelated spatial light modulator to provide a substantially enhanced image of the spectrum from the spectrum former to the reflective pixelated spatial light modulator.

49. The method of claim 45 wherein the reflective pixelated spatial light modulator is a first reflective pixelated spatial light modulator, and wherein the method further comprises reflecting the modified light beam off a second reflective spatial light modulator operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the second reflective pixelated spatial light modulator to reflect the desired segment of light in one direction and deflect other light in the spectrum in at least one other direction.

50. The method of claim 48 wherein the method further comprises passing the modified light beam by an optical projection device located downstream from the reflective pixelated spatial light modulator to project light as a directed light beam.

51. The method of claim 45 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of at least one of a known lamp, a cathode ray tube image display device, a light emissive image display device and a source of optical radiation.

52. The method of claim 45 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy corresponding to a desired natural ambient lighting scenario.

53. The method of claim 45 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy for disease treatment.

54. The method of claim 45 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy for photodynamic therapy.

55. The method of claim 45 wherein the desired segment is selected to substantially mimic a spectral output and a wavelength dependent intensity distribution of output energy for disease diagnosis.

56. The method of claim 45 wherein the reflective pixelated spatial light modulator is a digital micromirror device.

58. The method of claim 57 wherein the method further comprises emitting the light beam from a light source located in a same housing as and upstream from the spectrum former, and wherein the spectrum former comprises at least one of a prism and a diffraction grating.

59. The method of claim 58 wherein the pixelated spatial light modulator is a first pixelated spatial light modulator, and wherein light reflected from the first pixelated spatial light modulator is directed to a second pixelated spatial light modulator operably connected to at least one controller containing computer-implemented programming that controls the on/off pattern of pixels in the second pixelated spatial light modulator to reflect the desired segment of light in one direction and deflect other light in the spectrum in at least one other direction.

60. The method of claim 59 wherein the method further comprises an optical projection device located downstream from at least one of the first pixelated spatial light modulator and the second pixelated spatial light modulator to project light as a directed light beam.

45. A method of lighting a scene comprising:

a) directing a light beam along a light path and through a spectrum former to provide a spectrum from the light beam traveling;

b) reflecting the spectrum off a reflective pixelated spatial light modulator that is operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the reflective pixelated spatial light modulator, wherein the reflecting comprises reflecting a desired segment of light in the spectrum in a first reflected light path that is not back to the spectrum former and reflecting substantially all other light impinging on the reflective pixelated spatial light modulator in at least one second reflected light path that is not back to the spectrum former, to provide a modified light beam consisting essentially of a selected spectral output and a selected wavelength dependent intensity distribution.

57. A method of lighting a scene comprising:

a) directing a light beam along a light path and through a spectrum former to provide a spectrum from the light beam traveling; and

,

b) passing the spectrum via a pixelated spatial light modulator located downstream from and optically connected to the spectrum former, the pixelated spatial light modulator operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the pixelated spatial light modulator, wherein the on/off pattern is set to pass a desired segment of light in the spectrum in one direction and interrupt other light in the spectrum in at least one other direction, to provide a modified light beam consisting essentially of a selected spectral output and a selected wavelength dependent intensity distribution, and wherein the method does not comprise passing the spectrum by an optical element between the spectrum former and the pixelated spatial light modulator that provides an enhanced image of the spectrum from the spectrum former to the pixelated spatial light modulator.

61. A method of emitting modified light consisting essentially of a desired selected spectral output and a desired wavelength dependent intensity distribution from a stand alone luminaire, the method comprising:

a) emitting light from a high output light source located in a housing of the luminaire;

b) passing the light by a spectrum former optically connected to and downstream from the light source to provide a spectrum from a light beam emitted from the light source;

c) passing the spectrum by an optical element connected to and downstream from the spectrum former to provide an enhanced image of the spectrum;

d) reflecting the spectrum off a reflective pixelated spatial light modulator that is operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the reflective pixelated spatial light modulator, wherein the reflecting comprises reflecting a desired segment of light in the spectrum in a first reflected light path that is not back to the spectrum former and reflecting substantially all other light impinging on the reflective pixelated spatial light modulator in at least one second reflected light path that is not back to the spectrum former, to provide a modified light beam consisting essentially of a selected spectral output and a selected wavelength dependent intensity distribution; and

,

e) passing the modified light beam by a projection system optically connected to and downstream from the reflective pixelated spatial light modulator in the first direction, wherein the projection system projects the modified light beam from the luminaire as a directed light beam.

62. The method of claim 61 wherein the method further comprises reflecting the desired segment of light to a detector optically connected to and downstream from the reflective pixelated spatial light modulator, the detector located in the second reflected light path and operably connected to the controller, wherein the controller contains computer-implemented programming able to determine from the detector whether the desired segment contains the desired selected spectral output and the desired wavelength dependent intensity distribution, and therefrom determining whether the first segment contains the desired selected spectral output and the desired wavelength dependent intensity distribution.

63. The method of claim 62 wherein the method further comprises adjusting the on/off pattern of pixels in the reflective pixelated spatial light modulator to improve the correspondence between the desired segment and the desired selected spectral output and the desired wavelength dependent intensity distribution.

64. The method of claim 61 or 63 wherein the method further comprises removing undesired energy emitted from the light source toward at least one of the reflective pixelated spatial light modulator, the optical element, and the spectrum former, the removing effected via a heat removal element operably connected to the light source.

65. The method of claim 61 wherein the reflective pixelated spatial light modulator is a first reflective pixelated spatial light modulator, and wherein the desired segment is directed to a second spatial light modulator operably connected to at least one controller containing computer-implemented programming that controls an on/off pattern of pixels in the second reflective pixelated spatial light modulator to provide an improved desired selected spectral output and desired wavelength dependent intensity distribution.

66. The method of claim 61 or 63 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired portion of a wavelength dependent distribution of output energy of at least one of a known lamp, a cathode ray tube image display device, a light emissive image display device and a source of optical radiation.

67. The method of claim 61 or 63 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy corresponding to a desired natural ambient lighting scenario.

68. The method of claim 61 or 63 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy for disease treatment.

69. The method of claim 61 or 63 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy for photodynamic therapy.

70. The method of claim 61 or 63 wherein the desired selected spectral output and desired wavelength dependent intensity distribution substantially mimic a desired wavelength dependent distribution of output energy for disease diagnosis.

71. The method of claim 64 wherein the heat removal element is located between the lamp and the first spatial light modulator.

72. The method of claim 64 wherein the heat removal element is located between the lamp and the spectrum former.

73. The method of claim 64 wherein the heat removal element comprises a dichroic mirror.

74. The method of claim 64 wherein the undesired energy is directed to an energy absorbing surface and thermally conducted to a radiator.

75. The method of claim 61 or 63 wherein the method further comprises passing the desired segment by a spectral recombiner optically connected to and located downstream from the reflective pixelated spatial light modulator.