Contactless Multispectral Biometric Capture

• US 20090245591A1
• Filed: 06/10/2008
• Published: 10/01/2009
• Est. Priority Date: 07/19/2006
• Status: Active Grant

• Current Assignee: HID Global Corporation (Assa Abloy AB)
• Original Assignee: Lumidigm Incorporated (Assa Abloy AB)
• Inventors: Rowe, Robert K., Corcoran, Stephen P., Ennis, Matthew
• Granted Patent: US 7,995,808 B2
• Time in Patent Office: Days
• US Class Current: 382/115
• CPC Class Codes: G06V 10/143 Sensing or illuminating at different wavelengths
• CPC Class Codes: G06V 40/1312 direct reading, e.g. contactless acquisition

Abstract

A number of biometric systems and methods are disclosed. A system according to one embodiment includes an illumination subsystem, an imaging subsystem, and an analyzer. The illumination subsystem is disposed to illuminate a target space. The imaging subsystem is configured to image the target space under distinct optical conditions. The analyzer is provided in communication with the illumination subsystem, the imaging subsystem, and the three-dimensional subsystem. The analyzer also has instructions to operate the subsystems to collect substantially simultaneously a plurality of images of the object disposed at the predetermined spatial location under multispectral conditions.

Claims

1. A biometric system comprising:

one or more illumination sources configured to illuminate at least a portion of a target space;

a first imager configured to receive light from at least a portion of the target space under a first optical condition;

a second imager configured to receive light from at least a portion of the target space under a second optical condition, wherein the first optical condition is distinct from the second optical condition; and

an analyzer communicatively coupled with the one or more illumination sources and the plurality of imagers, wherein the analyzer is configured to control the operation of the one or more illumination sources, the first imager, and the second imager in order to produce a multispectral image of an object placed within the target space from the light received at first imager and the second imager.

2. The biometric system according to claim 1, wherein the analyzer is configured to control the first imager and the second imager wherein the first imager and the second imager provide an image of the target space substantially simultaneously.

3. The biometric system according to claim 1, wherein the target space is at least partially defined by a platen.

4. The biometric system according to claim 1, wherein the target space is adapted to receive a human hand.

5. The biometric system according to claim 1, wherein either or both of the first imager and the second imager comprise one or more optical elements selected from the group consisting of a color filter, a color filter array, a linear polarizer, a circular polarizer, a diffuser, a collimator, a grating, and a lens.

6. The biometric system according to claim 1, wherein the first imager is configured to receive light from a first subspace of the target space and the second imager is configured to receive light from a second subspace of the target space.

7. The biometric system according to claim 1, wherein the first imager is focused at a first focal plane and the second imager is focused at a second focal plane, wherein the first focal plane and the second focal plane are distinct.

8. The biometric system according to claim 1, wherein the target space is located within free space.

9. The biometric system according to claim 1, further comprising at least a first processor coupled with the first imager and a second processor coupled with the second imager.

10. The biometric system according to claim 1, further comprising a user interface configured to substantially indicate at least a portion of the target space to a user.

11. The biometric system according to claim 1, further comprising a presence detector configured to detect the presence of an object within the target space.

23. The biometric system according to claim 1, wherein the analyzer is further configured to control the imagers such that the imagers simultaneously receive light from the target space under multispectral conditions.

24. The biometric system according to claim 1, wherein the plurality of imagers are arranged substantially coplanar.

25. The biometric system according to claim 1, wherein the plurality of imagers include at least one wafer-level camera.

26. The biometric system according to claim 1, wherein the analyzer further comprises a plurality of processors, wherein each of the plurality of imagers are coupled with at least one processor.

27. The biometric system according to claim 1, wherein the target space is adapted to receive a human hand.

28. The biometric system according to claim 1, wherein a first subset of the plurality of imagers is focused on a first focal plane and a second subset of the plurality of imagers is focused on a second focal plane.

29. The biometric system according to claim 1, wherein the analyzer includes instructions for deriving spatially distributed multispectral characteristics from the one or more multispectral images.

30. The biometric system according to claim 1, wherein the one or more imagers receive light at a plurality of discrete wavelengths.

31. The biometric system according to claim 1, wherein the one or more illumination sources provide light at a plurality of distinct wavelengths.

32. The biometric system according to claim 1, wherein the target space is not defined by a platen.

12. A method for collecting a multispectral biometric image, the method comprising:

illuminating at least a portion of a target space;

receiving light from at least a portion of the target space under a first optical condition;

separately receiving light from at least a portion of the target space under a second optical condition substantially simultaneously as receiving light from the target space under the first optical condition, wherein the first optical condition and the second optical condition are distinct; and

deriving a multispectral image of an object within the target space from the light received under either or both of the first optical condition and the second optical condition.

13. The method according to claim 12, further comprising providing an indication of at least a portion of the target space.

14. The method according to claim 12, further comprising sensing the presence of an object within the target space.

15. The method according to claim 12, wherein the first optical condition and the second optical condition are selected from the group consisting of polarized light, total internally reflected light, light with a specific wavelength, light within a specific wavelength band, light from a subspace within the target space, and light from a focal plane within the target space.

16. The method according to claim 12, wherein a first imager provides a first image of at least a portion of the target space under the first optical condition and a second imager provides a second image of at least a portion of the target space under the second optical condition.

17. The method according to claim 16, wherein first image has a resolution greater than the resolution of the second image.

18. A biometric system comprising:

illumination means for illuminating a target space;

first imaging means for imaging at least a portion of the target space under a first optical condition and providing a first image;

second imaging means for imaging at least a portion of the target space under a second optical condition distinct from the first optical condition and providing a second image; and

processing means for controlling the illumination means, the first imaging means and the second imaging means, wherein the processing means is configured to derive a multispectral image from the first image and the second image.

19. The biometric system according to claim 18, further comprising presence sensing means for sensing the presence of an object within at least a portion of the target space.

20. The biometric system according to claim 18, wherein the first optical condition and the second optical condition is selected from the group consisting of polarized light, total internally reflected light, light with a specific wavelength, light within a specific wavelength band, light from a subspace within the target space, and light from a focal plane within the target space.

21. The biometric system according to claim 18, further comprising indication means for indicating at least a portion of the target space to a user.

22. A biometric system comprising:

one or more illumination sources configured to illuminate a target space;

a plurality of imagers configured to receive light from the target space under multispectral conditions, wherein each imager is configured to receive light from a different subspace of said target space; and

an analyzer communicatively coupled with the one or more illumination sources and the plurality of imagers, the analyzer configured to control the operation of the one or more illumination sources and the plurality of imagers in order to produce one or more multispectral image of an object placed within the target space from the light received at any or all the imagers.

33. A biometric system comprising:

one or more illumination sources configured to illuminate a target space;

a first imager that receives light from a first subspace of said target space under multispectral conditions;

a second imager that receives light from a second subspace of said target space under multispectral conditions, wherein the first imager and the second imager receive light substantially simultaneously; and

an analyzer communicatively coupled with the one or more illumination sources, the first imager, and the second imager, the analyzer configured to control the operation of the one or more illumination sources, the first imager, and the second imager in order to derive a multispectral image of an object placed within the target space from light received at either or both of the first imager and the second imager.

34. The biometric system according to claim 33, wherein said target space is defined in part by a platen.

35. The biometric system according to claim 33, wherein said target space is configured to receive a human hand.

36. The biometric system according to claim 33, wherein the first subspace and the second subspace comprise substantially the same subspace.

37. The biometric system according to claim 33, wherein the first subspace and the second subspace overlap.

38. The biometric system according to claim 33, wherein either or both of the first imager and the second imager comprise one or more optical element selected from the list consisting of color filters, color filter arrays, polarizers, diffusers, collimators, gratings, and lenses.

39. A method for collecting a biometric image comprising:

illuminating a target space with one or more illumination sources;

receiving light from a first subspace of said target space with a first imager;

receiving light from a second subspace of said target space with a second imager; and

deriving a multispectral image of at least a portion of an object within said target space from the light received at either or both of the first imager and the second imager.

40. The method according to claim 39, further comprising performing a biometric function with the multispectral image.

41. The method according to claim 39, further comprising performing a liveliness function with the multispectral image.

42. The method according to claim 39, further comprising performing a spoof-detection function with the multispectral image.

43. The method according to claim 39, wherein the receiving light from a first subspace of said target space with a first imager and the receiving light from a second subspace of said target space with a second imager occur substantially simultaneously.

44. The method according to claim 39, further comprising providing a user interface configured to substantially define at least portions of the target space.

45. The method according to claim 39, further comprising deriving spatially distributed multispectral characteristics from the multispectral image.

46. A biometric system comprising:

a platen adapted for placement of a purported skin site by an individual;

one or more illumination sources configured to illuminate the skin site;

a first imager configured to receive light from a first zone of said skin site under multispectral conditions;

a second imager configured to receive light from a second zone of said skin site under multispectral conditions; and

an analyzer communicatively coupled with the one or more illumination sources, the first imager, and the second imager, the analyzer configured to control the operation of the one or more illumination sources, the first imager, and the second imager in order to derive a multispectral image of the skin site from light received at either or both of the first imager and the second imager.

47. The biometric system according to claim 46, further comprising at least a first processor coupled with the first imager and a second processor coupled with the second imager.

48. The biometric system according to claim 46, wherein the analyzer included instructions to substantially simultaneously record images of the skin site with the first imager and the second imager.

49. The biometric system according to claim 46, wherein the first imager and the second imager may include a wafer-level camera.

50. A biometric system comprising:

one or more illumination sources configured to illuminate a target space;

a plurality of imagers configured to receive light from the target space under multispectral conditions, wherein at least one imager receives light with a multispectral condition distinct from the multispectral condition received with at least one other imager;

an analyzer communicatively coupled with the one or more illumination sources and the plurality of imagers, wherein the analyzer is configured to control the operation of the one or more illumination sources and the plurality of imagers in order to produce a multispectral image of an object placed within the target space from the light received at any or all the imagers.

51. The biometric system according to claim 50, wherein a multispectral condition is selected from the groups consisting of:

polarization, illumination angle, imaging angle, illumination wavelength or wavelengths, and imaging wavelength or wavelength.

52. The biometric system according to claim 50, wherein at least on imager of the plurality of imagers includes at least an optical element selected from the group consisting of:

a color filter, a color filter array, a polarizer, a diffuser, a collimator, a grating, and a lens.

53. The biometric system according to claim 50, wherein the analyzer includes instructions to substantially simultaneously record images of the skin site with at least two of the plurality of imagers.

54. The biometric system according to claim 50, further comprising a plurality of processors, wherein each imager of the plurality of imagers is coupled with one of the plurality of processors.

55. A biometric system comprising:

one or more illumination sources configured to illuminate a target space;

a first imager configured to receive light from said target space under a first optical condition;

a second imager configured to receive light from said target space under a second optical condition; and

an analyzer communicatively coupled with the one or more illumination sources, the first imager, and the second imager, the analyzer configured to control the operation of the one or more illumination sources, the first imager, and the second imager in order to derive a multispectral image of an object placed within the target space from light received at either or both of the first imager and the second imager.

56. The biometric system according to claim 55, wherein the difference between the first optical condition and the second optical condition is selected from the group consisting of:

a difference in polarization, a difference in illumination angle, a difference in imaging angle, a difference in illumination wavelength or wavelengths, and a difference in imaging wavelength or wavelength(s).

57. The biometric system according to claim 55, wherein the analyzer includes instructions to derive spatially distributed multispectral characteristics from the multispectral image.

58. The biometric system according to claim 55, further comprising at least a first processor coupled with the first imager and second processor coupled with the second imager.

59. A method for collecting a biometric image comprising:

illuminating a target space;

receiving light from said target space under a first optical condition;

receiving light from said target space under a second optical condition; and

deriving a multispectral image of an object within said target space from the light received at either or both of the first imager and the second imager.

60. The method according to claim 59, wherein the target space is exists in free space.

61. The method according to claim 59, further comprising deriving spatially distributed multispectral characteristics from the multispectral image.

62. The method according to claim 59, wherein the difference between the first optical condition and the second optical condition are selected from the group consisting of:

a difference in polarization, a difference in illumination angle, a difference in imaging angle, a difference in illumination wavelength or wavelengths, and a difference in imaging wavelength or wavelengths.

63. The method according to claim 59, further comprising performing a biometric function with the multispectral image.

64. The method according to claim 59, further comprising performing a liveliness function with the multispectral image.

65. The method according to claim 59, further comprising performing a spoof-detection function with the multispectral image.

66. The method according to claim 59, wherein the receiving light from said target space under a first optical condition and the receiving light from said target space under a second optical condition occur substantially simultaneously.

67. The method according to claim 59, further comprising providing a user interface configured to substantially define at least portions of the target space.

68. A contactless biometric system comprising:

one or more illumination sources configured to illuminate a target space located in free space;

one or more imagers configured to collect light from at least a portion of the target space under multispectral conditions;

an analyzer communicatively coupled with the one or more illumination sources and the one or more imagers, the analyzer configured to control the operation of the one or more illumination sources and the one or more imagers in order to derive a multispectral image of an object placed within the target space and imaged by the one or more imagers.

69. The contactless biometric system according to claim 68, wherein the target space is dimensioned to receive a human hand.

70. The contactless biometric system according to claim 68, further comprising a user interface configured to substantially delineate the relative dimension of portions of the target space within free space.

71. The contactless biometric system according to claim 68, further comprising a user interface configured to display a holographic image of hand within the target space.

72. The contactless biometric system according to claim 68, further comprising a user interface that includes one or more light sources configured to illuminate portions of an object when the object is placed within the target space.

73. The contactless biometric system according to claim 68, further comprising a user interface that includes a speaker that provides an audible indication when an object is placed substantially within the target space.

74. The contactless biometric system according to claim 68, wherein the one or more imagers includes at least a first imager and a second imager, wherein the first imager is focused at a first focal plane within the target space and the second imager is focused at a second focal plane within the target space distinct from the first focal plane.

75. The contactless biometric system according to claim 68, wherein at least one of the plurality of imagers includes an auto focus.

76. The contactless biometric system according to claim 68, wherein at least one of the plurality of imagers includes a low numerical aperture.

77. The contactless biometric system according to claim 68, wherein at least two of the plurality of imagers collect light from at least a portion of the target space substantially simultaneously.

78. The contactless biometric system according to claim 68, wherein at least two of the plurality of imagers collect light from substantially the same portions of the target space under distinct multispectral conditions.

79. The contactless biometric system according to claim 68, wherein at least two of the plurality of imagers collect light from substantially distinct portions of the target space.

80. A method for collecting a biometric image comprising:

detecting the presence of an object within a target space located in free space;

illuminating the object within the target space with one or more illumination sources;

receiving light from the target space at one or more imagers under multispectral conditions; and

deriving a multispectral image of the object within said target space from the light received at the one or more imagers.

81. The method according to claim 80, further comprising providing a visual indication of portions of the target space within free space.

82. The method according to claim 80, further comprising providing a holographic image of a hand positioned substantially within the target space.

83. The method according to claim 80, further comprising providing an indication when the object is detected within the target space, wherein the indication is either or both of an audible indication and a visual indication.

84. The method according to claim 80, determining the identity of an individual from the multispectral image.

85. A contactless biometric system comprising:

an illumination subsystem disposed to illuminate a predetermined spatial location in free space;

an imaging subsystem disposed to collect light emanating from the predetermined spatial location;

sensing means for sensing when a purported skin site is placed substantially within the predetermined spatial location; and

an analyzer in communication with the illumination subsystem, the imaging subsystem, and the sensing subsystem, wherein the analyzer comprises instructions to operate the illumination subsystem, the imaging subsystem, and the sensing subsystem to derive a multispectral image of an object placed within the target space and imaged by the one or more imagers.

86. The contactless biometric system according to claim 85, wherein the sensing means and the imaging subsystem comprise a single subsystem.

87. The contactless biometric system according to claim 85, wherein the sensing means includes stereoscopic imagers.

88. The contactless biometric system according to claim 85, wherein the sensing means includes stereoscopic illuminators.

89. The contactless biometric system according to claim 85, wherein the sensing means includes at least one imager and a color filter array with a plurality of color mosaics, wherein each pixel of the imager corresponds to one of the plurality of color mosaics such that each pixel detects light associated with the corresponding color, and wherein the analyzer includes instructions to monitor the levels of blue light received at the imager through the color filter array and compute a mathematical function on the levels of blue light in proportion with levels of other light.

90. The contactless biometric system according to claim 89, wherein the color filter array is a Bayer filter array.

91. The contactless biometric system according to claim 85, wherein the imaging subsystem comprises at least a first imager and a second imager configured to image light from the predetermined spatial location substantially simultaneously.

92. A biometric system comprising:

one or more illumination sources configured to illuminate a target space located in free space;

one or more imagers configured to collect light from at least a portion of the target space under multispectral conditions;

a user interface configured to communicate the proximate location of the target space in free space; and

an analyzer communicatively coupled with the one or more illumination sources and the one or more imagers, the analyzer includes instructions to illuminate the target space with the one or more illumination sources, and derive a multispectral image of an object placed within the target space and imaged by the one or more imagers.

93. The biometric system according to claim 92, further comprising sensing means includes stereoscopic imagers.

94. The biometric system according to claim 92, wherein the sensing means for sensing when a purported skin site is placed substantially within the target space.

95. The biometric system according to claim 92, wherein the user interface is configured to display a holographic image of hand within the target space.

96. The biometric system according to claim 92, wherein the user interface includes one or more light sources configured to illuminate portions of an object when the object is placed within the target space.

97. A method for collecting a biometric image comprising:

providing an indication of the proximate location of a target space in free space;

illuminating an object within the target space with one or more illumination sources;

receiving light from the target space at one or more imagers under multispectral conditions; and

deriving a multispectral image of the object within said target space from the light received at the one or more imagers.

98. The method according to claim 97, further comprising performing a biometric function with the multispectral image.

99. The method according to claim 97, wherein the providing the an indication of the proximate location of a target space in free space includes providing a at least a portion of a holographic image of a hand within the target space.

100. The method according to claim 97, wherein the providing the an indication of the proximate location of a target space in free space includes providing a at least a portion of a holographic image of a finger within the target space.

101. The method according to claim 97, wherein the providing the an indication of the proximate location of a target space in free space includes illuminating at least portions of the target space.

102. The method according to claim 97, wherein the providing the an indication of the proximate location of a target space in free space includes illuminating portions of an object when the object is placed within the target space.

103. The method according to claim 97, further comprises providing an audible indication when an object is at least partially within the target space.

104. The method according to claim 97, further comprises providing a visual indication when an object is at least partially within the target space.

105. A biometric system comprising:

conveying means for conveying an indication of the proximate location of a target space in free space;

illuminating means for illuminating at least a portion of the target space;

imaging means for receiving light from the target space under multispectral conditions;

logic means for deriving a multispectral image of an object within said target space from the light received by the imaging means.

106. A biometric system comprising:

a platen configured to receive a human hand;

one or more illumination sources configured to illuminate a hand placed on the platen;

a first imager configured to receive light from a first portion of the hand under multispectral conditions;

a second imager configured to receive light from a second portion of the hand under multispectral conditions; and

an analyzer communicatively coupled with the one or more illumination sources, the first imager, and the second imager, the analyzer configured to control the operation of the one or more illumination sources, the first imager, and the second imager in order to derive a multispectral image of the first portion of the hand from light received at first imager and derive a multispectral image of the second portion of the hand from light received at second imager.

107. The biometric system according to claim 106, wherein the first imager and the second imager analyze different characteristics of the hand.

108. A biometric system comprising:

one or more illumination sources configured to illuminate a hand placed substantially within target space in free space;

a plurality of imagers configured to receive light from portions of a hand placed substantially within the target space under multispectral conditions;

an analyzer communicatively coupled with the one or more illumination sources and the plurality of imagers, the analyzer configured to control the operation of the one or more illumination sources and the plurality of imagers in order to derive a multispectral image of the portions of the hand from light received at the plurality of imagers.

109. The biometric system according to claim 108, wherein the target space is bounded at least in part by a platen such that a hand may rest substantially on the platen.

110. The biometric system according to claim 108, wherein the plurality of imagers include a first imager and a second imager, the first imager is focused on a first portion of a hand, and the second imager is focused on a second portion of a hand.

111. A method for collecting a biometric image of a hand comprising:

providing a target space located in free space for the placement of a human hand by an individual;

illuminating a hand within the target space using one or more illumination sources;

receiving light from the hand under multispectral conditions using one or more imagers; and

deriving at least one multispectral image of at least one portion of the hand within the target space from the received light.