DISPLAY DEVICE CALIBRATION SYSTEM

• US 20080316222A1
• Filed: 06/21/2007
• Published: 12/25/2008
• Est. Priority Date: 06/21/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Chen, Wei, Marcu, Gabriel G.
• Granted Patent: US 7,777,755 B2
• Time in Patent Office: Days
• US Class Current: 345/589
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309

Abstract

A display device calibration system is provided. The overall color response of a display family is characterized, and the idiosyncratic color response characteristics of the display family are determined. The idiosyncratic color response characteristics of the display family are related to respective idiosyncratic color response points. Individual idiosyncratic color response point values for an individual member of the display family are determined. The color response of the individual member of the display family is specified from the individual idiosyncratic color response point values of the individual member of the display family and the overall color response of the display family.

Claims

1. A display device calibration system, comprising:

characterizing the overall color response of a display family;

determining the idiosyncratic color response characteristics of the display family;

relating the idiosyncratic color response characteristics of the display family to respective idiosyncratic color response points;

determining individual idiosyncratic color response point values for an individual member of the display family; and

specifying the color response of the individual member of the display family from;

the individual idiosyncratic color response point values of the individual member of the display family; and

the overall color response of the display family.

2. The system as claimed in claim 1 further comprising representing the overall color response of the display family as a function that defines an n-dimensional curve.

3. The system as claimed in claim 1 further comprising representing the overall color response of the display family as a function that defines a multi-dimensional surface.

4. The system as claimed in claim 1 further comprising:

representing the overall color response of the display family as a function that defines an n-dimensional curve; and

conforming the function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

5. The system as claimed in claim 1 further comprising:

representing the overall color response of the display family as a function that defines a multi-dimensional surface; and

conforming the function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

6. The system as claimed in claim 1 further comprising utilizing the overall color response and the idiosyncratic color response points for gray level calibration of the individual member of the display family.

7. The system as claimed in claim 1 further comprising utilizing the overall color response and the idiosyncratic color response points for color calibration of the individual member of the display family.

8. The system as claimed in claim 1 wherein the overall color response and the idiosyncratic color response points are contained within substantially the same range.

9. The system as claimed in claim 1 further comprising calibrating and controlling a TFT LCD display.

10. The system as claimed in claim 1 further comprising utilizing the color response of the individual member of the display family to derive intermediate values between measured individual idiosyncratic color response point values of the individual member.

11. The system as claimed in claim 1 further comprising utilizing the color response of the individual member of the display family to apply an inverse compensation to a video signal.

12. The system as claimed in claim 1 further comprising determining independent color responses ƒ

_R, ƒ

_G, and ƒ

_B for each R, G, and B color channel.

13. The system as claimed in claim 1 further comprising defining a characteristic of the displays as a function of another characteristic of the displays.

14. The system as claimed in claim 1 further comprising characterizing the color response of an individual member of the display family in less time than the time for measuring all the color response point values of the individual member of the display family by measuring only a reduced set of points that includes substantially the individual idiosyncratic color response points.

15. The system as claimed in claim 1 further comprising storing information concerning the overall color response of the display family and information concerning the idiosyncratic color response characteristics of the display family externally to individual members of the display family.

16. The system as claimed in claim 1 further comprising storing information concerning the overall color response of the display family and information concerning the idiosyncratic color response characteristics of the display family internally in individual members of the display family.

17. The system as claimed in claim 1 wherein characterizing the overall color response of a display family and determining the idiosyncratic color response characteristics of the display family further comprise:

making measurements on members of the display family; and

statistically analyzing the measurements to;

derive the overall color response of the display family; and

the idiosyncratic color response characteristics of the display family.

18. The system as claimed in claim 1 wherein characterizing the overall color response of a display family and determining the idiosyncratic color response characteristics of the display family further comprise:

making measurements of color response measurement points of a predetermined number of members of the display family; and

determining which of the measurement points are common to the overall color response, and which of the measurement points are idiosyncratic, by;

determining the standard deviations of the measurement point measurements;

determining which of the measurements produce the lower standard deviations and assigning them to the overall color response characterization, and

determining which of the measurements produce the higher standard deviations and assigning them to the idiosyncratic color response points.

19. The system as claimed in claim 1 further comprising determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall color response of the display family that is less than a predetermined σ

value.

20. The system as claimed in claim 1 further comprising determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall color response of the display family that is less than a predetermined σ

value, by identifying those color response points in the overall color response of the display family that have σ

values above a predetermined value and incorporating those identified color response points into the idiosyncratic color response characteristics of the display family.

21. The system as claimed in claim 1 further comprising relaxing production constraints on production factors that are substantially independent of the idiosyncratic color response points.

22. A display device calibration system, comprising:

characterizing the overall objective color response of a display family;

determining the idiosyncratic color response characteristics of the display family;

relating the idiosyncratic color response characteristics of the display family to respective idiosyncratic color response points;

determining individual idiosyncratic color response point values for an individual member of the display family;

uniquely specifying the color response of the individual member of the display family from;

the individual idiosyncratic color response point values of the individual member of the display family; and

the overall objective color response of the display family by applying the individual idiosyncratic color response point values of the individual member of the display family to the overall objective color response of the display family; and

reconstructing at least a portion of the color response of the individual member of the display family from the individual idiosyncratic color response point values of the individual member of the display family.

23. The system as claimed in claim 22 further comprising representing the overall objective color response of the display family as a continuous mathematical function that defines an n-dimensional curve.

24. The system as claimed in claim 22 further comprising representing the overall objective color response of the display family as a continuous mathematical function that defines a multi-dimensional surface.

25. The system as claimed in claim 22 further comprising:

representing the overall objective color response of the display family as a continuous mathematical function that defines an n-dimensional curve; and

conforming the continuous mathematical function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

26. The system as claimed in claim 22 further comprising:

representing the overall objective color response of the display family as a continuous mathematical function that defines a multi-dimensional surface; and

conforming the continuous mathematical function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

27. The system as claimed in claim 22 further comprising utilizing the overall objective color response and the idiosyncratic color response points for gray level calibration of the individual member of the display family.

28. The system as claimed in claim 22 further comprising utilizing the overall objective color response and the idiosyncratic color response points for color calibration of the individual member of the display family.

29. The system as claimed in claim 22 wherein the overall objective color response and the idiosyncratic color response points are contained within substantially the same range.

30. The system as claimed in claim 22 further comprising calibrating and controlling a TFT LCD display.

31. The system as claimed in claim 22 further comprising utilizing the color response of the individual member of the display family to derive intermediate values between measured individual idiosyncratic color response point values of the individual member.

32. The system as claimed in claim 22 further comprising utilizing the color response of the individual member of the display family to apply an inverse compensation to a video signal.

33. The system as claimed in claim 22 further comprising determining independent color response functions ƒ

_R, ƒ

_G, and ƒ

_B for each R, G, and B color channel.

34. The system as claimed in claim 22 further comprising defining predetermined characteristics of the displays as functions of other characteristics of the displays.

35. The system as claimed in claim 22 further comprising characterizing the color response of an individual member of the display family in less time than the time for measuring all the color response point values of the individual member of the display family by measuring only a reduced set of points that includes substantially the individual idiosyncratic color response points.

36. The system as claimed in claim 22 further comprising storing information concerning the overall objective color response of the display family and information concerning the idiosyncratic color response characteristics of the display family externally to individual members of the display family.

37. The system as claimed in claim 22 further comprising storing information concerning the overall objective color response of the display family and information concerning the idiosyncratic color response characteristics of the display family internally in individual members of the display family.

38. The system as claimed in claim 22 wherein characterizing the overall objective color response of a display family and determining the idiosyncratic color response characteristics of the display family further comprise:

making measurements on a subset of members of the display family; and

statistically analyzing the measurements to;

derive the overall objective color response of the display family; and

the idiosyncratic color response characteristics of the display family.

39. The system as claimed in claim 22 wherein characterizing the overall objective color response of a display family and determining the idiosyncratic color response characteristics of the display family further comprise:

making measurements of color response measurement points of a subset of members of the display family; and

determining which of the measurement points are common to the overall objective color response, and which of the measurement points are idiosyncratic, by;

determining the standard deviations of the measurement point measurements;

determining which of the measurements produce the lower standard deviations and assigning them to the overall objective color response characterization, and

determining which of the measurements produce the higher standard deviations and assigning them to the idiosyncratic color response points.

40. The system as claimed in claim 22 further comprising determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall objective color response of the display family that is less than a predetermined σ

value.

41. The system as claimed in claim 22 further comprising determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall objective color response of the display family that is less than a predetermined σ

value, by identifying those color response points in the overall objective color response of the display family that have σ

values above a predetermined value and incorporating those identified color response points into the idiosyncratic color response characteristics of the display family.

42. The system as claimed in claim 22 further comprising relaxing production constraints on production factors that are substantially independent of the idiosyncratic color response points.

43. A display device calibration system, comprising:

means for characterizing the overall color response of a display family;

means for determining the idiosyncratic color response characteristics of the display family;

circuitry for relating the idiosyncratic color response characteristics of the display family to respective idiosyncratic color response points;

means for determining individual idiosyncratic color response point values for an individual member of the display family; and

circuitry for specifying the color response of the individual member of the display family from;

the individual idiosyncratic color response point values of the individual member of the display family; and

the overall color response of the display family.

44. The system as claimed in claim 43 further comprising circuitry for representing the overall color response of the display family as a function that defines an n-dimensional curve.

45. The system as claimed in claim 43 further comprising circuitry for representing the overall color response of the display family as a function that defines a multi-dimensional surface.

46. The system as claimed in claim 43 further comprising:

circuitry for representing the overall color response of the display family as a function that defines an n-dimensional curve; and

circuitry for conforming the function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

47. The system as claimed in claim 43 further comprising:

circuitry for representing the overall color response of the display family as a function that defines a multi-dimensional surface; and

circuitry for conforming the function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

48. The system as claimed in claim 43 further comprising circuitry for utilizing the overall color response and the idiosyncratic color response points for gray level calibration of the individual member of the display family.

49. The system as claimed in claim 43 further comprising circuitry for utilizing the overall color response and the idiosyncratic color response points for color calibration of the individual member of the display family.

50. The system as claimed in claim 43 wherein the overall color response and the idiosyncratic color response points are contained within substantially the same range.

51. The system as claimed in claim 43 further comprising circuitry for calibrating and controlling a TFT LCD display.

52. The system as claimed in claim 43 further comprising circuitry for utilizing the color response of the individual member of the display family to derive intermediate values between measured individual idiosyncratic color response point values of the individual member.

53. The system as claimed in claim 43 further comprising circuitry for utilizing the color response of the individual member of the display family to apply an inverse compensation to a video signal.

54. The system as claimed in claim 43 further comprising circuitry for determining independent color responses ƒ

_R, ƒ

_G, and ƒ

_B for each R, G, and B color channel.

55. The system as claimed in claim 43 further comprising circuitry for defining a characteristic of the displays as a function of another characteristic of the displays.

56. The system as claimed in claim 43 further comprising means for characterizing the color response of an individual member of the display family in less time than the time for measuring all the color response point values of the individual member of the display family by measuring only a reduced set of points that includes substantially the individual idiosyncratic color response points.

57. The system as claimed in claim 43 further comprising means for storing information concerning the overall color response of the display family and information concerning the idiosyncratic color response characteristics of the display family externally to individual members of the display family.

58. The system as claimed in claim 43 further comprising means for storing information concerning the overall color response of the display family and information concerning the idiosyncratic color response characteristics of the display family internally in individual members of the display family.

59. The system as claimed in claim 43 wherein the means for characterizing the overall color response of a display family and the means for determining the idiosyncratic color response characteristics of the display family further comprise:

means for making measurements on members of the display family; and

circuitry for statistically analyzing the measurements to;

derive the overall color response of the display family; and

the idiosyncratic color response characteristics of the display family.

60. The system as claimed in claim 43 wherein the means for characterizing the overall color response of a display family and the means for determining the idiosyncratic color response characteristics of the display family further comprise:

means for making measurements of color response measurement points of a predetermined number of members of the display family; and

circuitry for determining which of the measurement points are common to the overall color response, and which of the measurement points are idiosyncratic, by;

determining the standard deviations of the measurement point measurements;

determining which of the measurements produce the lower standard deviations and assigning them to the overall color response characterization, and

determining which of the measurements produce the higher standard deviations and assigning them to the idiosyncratic color response points.

61. The system as claimed in claim 43 further comprising circuitry for determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall color response of the display family that is less than a predetermined σ

value.

62. The system as claimed in claim 43 further comprising circuitry for determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall color response of the display family that is less than a predetermined σ

value, by identifying those color response points in the overall color response of the display family that have σ

values above a predetermined value and incorporating those identified color response points into the idiosyncratic color response characteristics of the display family.

63. The system as claimed in claim 43 further comprising means for relaxing production constraints on production factors that are substantially independent of the idiosyncratic color response points.

64. A display device calibration system, comprising:

means for characterizing the overall objective color response of a display family;

means for determining the idiosyncratic color response characteristics of the display family;

circuitry for relating the idiosyncratic color response characteristics of the display family to respective idiosyncratic color response points;

means for determining individual idiosyncratic color response point values for an individual member of the display family;

circuitry for uniquely specifying the color response of the individual member of the display family from;

the individual idiosyncratic color response point values of the individual member of the display family; and

the overall objective color response of the display family by applying the individual idiosyncratic color response point values of the individual member of the display family to the overall objective color response of the display family; and

circuitry for reconstructing at least a portion of the color response of the individual member of the display family from the individual idiosyncratic color response point values of the individual member of the display family.

65. The system as claimed in claim 64 further comprising circuitry for representing the overall objective color response of the display family as a continuous mathematical function that defines an n-dimensional curve.

66. The system as claimed in claim 64 further comprising circuitry for representing the overall objective color response of the display family as a continuous mathematical function that defines a multi-dimensional surface.

67. The system as claimed in claim 64 further comprising:

circuitry for representing the overall objective color response of the display family as a continuous mathematical function that defines an n-dimensional curve; and

circuitry for conforming the continuous mathematical function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

68. The system as claimed in claim 64 further comprising:

circuitry for representing the overall objective color response of the display family as a continuous mathematical function that defines a multi-dimensional surface; and

circuitry for conforming the continuous mathematical function to substantially match the individual idiosyncratic color response points of the individual member of the display family.

69. The system as claimed in claim 64 further comprising circuitry for utilizing the overall objective color response and the idiosyncratic color response points for gray level calibration of the individual member of the display family.

70. The system as claimed in claim 64 further comprising circuitry for utilizing the overall objective color response and the idiosyncratic color response points for color calibration of the individual member of the display family.

71. The system as claimed in claim 64 wherein the overall objective color response and the idiosyncratic color response points are contained within substantially the same range.

72. The system as claimed in claim 64 further comprising circuitry for calibrating and controlling a TFT LCD display.

73. The system as claimed in claim 64 further comprising circuitry for utilizing the color response of the individual member of the display family to derive intermediate values between measured individual idiosyncratic color response point values of the individual member.

74. The system as claimed in claim 64 further comprising circuitry for utilizing the color response of the individual member of the display family to apply an inverse compensation to a video signal.

75. The system as claimed in claim 64 further comprising circuitry for determining independent color response functions ƒ

_R, ƒ

_G, and ƒ

_B for each R, G, and B color channel.

76. The system as claimed in claim 64 further comprising circuitry for defining predetermined characteristics of the displays as functions of other characteristics of the displays.

77. The system as claimed in claim 64 further comprising means for characterizing the color response of an individual member of the display family in less time than the time for measuring all the color response point values of the individual member of the display family by measuring only a reduced set of points that includes substantially the individual idiosyncratic color response points.

78. The system as claimed in claim 64 further comprising means for storing information concerning the overall objective color response of the display family and information concerning the idiosyncratic color response characteristics of the display family externally to individual members of the display family.

79. The system as claimed in claim 64 further comprising means for storing information concerning the overall objective color response of the display family and information concerning the idiosyncratic color response characteristics of the display family internally in individual members of the display family.

80. The system as claimed in claim 64 wherein the means for characterizing the overall objective color response of a display family and the means for determining the idiosyncratic color response characteristics of the display family further comprise:

making measurements on a subset of members of the display family; and

statistically analyzing the measurements to;

derive the overall objective color response of the display family; and

the idiosyncratic color response characteristics of the display family.

81. The system as claimed in claim 64 wherein the means for characterizing the overall objective color response of a display family and the means for determining the idiosyncratic color response characteristics of the display family further comprise:

means for making measurements of color response measurement points of a subset of members of the display family; and

circuitry for determining which of the measurement points are common to the overall objective color response, and which of the measurement points are idiosyncratic, by;

determining the standard deviations of the measurement point measurements;

determining which of the measurements produce the lower standard deviations and assigning them to the overall objective color response characterization, and

determining which of the measurements produce the higher standard deviations and assigning them to the idiosyncratic color response points.

82. The system as claimed in claim 64 further comprising circuitry for determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall objective color response of the display family that is less than a predetermined σ

value.

83. The system as claimed in claim 64 further comprising circuitry for determining the idiosyncratic color response characteristics of the display family to achieve a standard deviation σ

in the overall objective color response of the display family that is less than a predetermined σ

value, by identifying those color response points in the overall objective color response of the display family that have σ

values above a predetermined value and incorporating those identified color response points into the idiosyncratic color response characteristics of the display family.

84. The system as claimed in claim 64 further comprising means for relaxing production constraints on production factors that are substantially independent of the idiosyncratic color response points.