Method and apparatus for positioning subjects before a single camera

• US 6,064,752 A
• Filed: 11/04/1997
• Issued: 05/16/2000
• Est. Priority Date: 11/04/1997
• Status: Expired due to Term

• Current Assignee: Sensar, Inc. (Advent International Corporation)
• Original Assignee: Sensar, Inc. (Advent International Corporation)
• Inventors: O'Brien, Anthony, Negin, Michael, Dela Rosa, Guy, Rozmus, J. Michael
• Primary Examiner(s): MEHTA, BHAVESH M
• Application Number:
  US08/964,452
• Time in Patent Office: 924 Days
• Field of Search: 382/100, 382/115-118, 340/439, 340/575, 340/576, 351/200, 351/205, 351/208-211, 351/213, 351/219, 351/221, 351/222, 351/206, 351/207, 348/77, 348/78, 348/131, 348/132, 348/306, 348/308
• US Class Current: 382/117
• CPC Class Codes: A61B 5/1176 Recognition of faces
• CPC Class Codes: G06V 40/19 Sensors therefor

Abstract

A system and method of positioning a head of a subject to be photographed by a single camera uses a mirror and at least one collimated light beam. The single camera is positioned so that there is a selected specific location in space within a field of view of the camera at which the head or eye of the subject is desired to be positioned. A light source directs a collimated light beam or light sheet so that the light beam or light sheet intersects a line running from the mirror through the selected specific location in space and can be seen by an eye at the selected specific location in space that is looking at the mirror. The user is told to position his head across from the mirror and move his head until he sees the collimated light beam or light sheet and his eye in the mirror. When the subject is so positioned the single camera can take an image of the eye from which the subject can be identified. If desired a second mirror can be used in place of the light source.

Claims

1. A method of positioning an eye of a subject to be photographed by a camera comprising the steps of:

a. selecting a specific location in space within a field of view of the camera at which an eye of the subject is desired to be positioned;

b. providing a mirror at a fixed distance from the selected specific location in space such that the subject can see a reflected image of his eye at a particular spot in the mirror only when his line of sight is a segment of a line that passes through the selected specific location in space;

c. directing a collimated light beam in a manner so that the light beam passes through the selected specific location in space; and

d. instructing the subject to position his head so that he sees an image of his eye at a particular spot in the mirror and also sees the collimated light beam.

2. The method of claim 1 also comprising placing a target on the mirror which defines a particular spot where at least a portion of the reflected image is desired to be positioned.

3. The method of claim 1 also comprising placing a luminous indicator in the mirror which defines a particular spot where at least a portion of the reflected image is desired to be positioned.

4. The method of claim 1 wherein the mirror has a concave surface for magnification of the reflected image.

5. The method of claim 1 wherein the camera detects infrared light.

6. The method of claim 1 wherein the mirror is a partially-transparent mirror and the camera is positioned to receive light reflected from the eye of the subject that passes through the mirror.

7. The method of claim 1 wherein the mirror is a cold mirror and a camera is positioned to receive infrared light reflected from the eye of the subject that passes through the mirror.

8. The method of claim 1 also comprising the step of detecting a specular reflection of the light beam from at least one eye of the subject or from at least one lens of eyeglasses worn by the subject.

9. The method of claim 8 wherein the specular reflection is detected by a photodetector.

10. The method of claim 8 wherein the specular reflection is detected by the camera.

11. The method of claim 8 also comprising the step of producing an audible tone when the specular reflection is detected.

12. The method of claim 8 also comprising the step of activating a luminous indicator when the specular reflection is detected.

13. A method of positioning an eye of a subject to be photographed by a camera comprising the steps of:

a. selecting a specific location in space within a field of view of the camera at which an eye of the subject is desired to be positioned;

b. providing a first mirror at a fixed distance from the selected specific location in space such that the subject can see a first reflected image of his eye at a particular spot in the mirror only when his line of sight is a segment of a line that passes through the selected specific location in space;

c. providing a second mirror at a fixed distance from the selected specific location in space such that the subject can see a second reflected image of his eye at a particular spot in this second mirror only when his line of sight is a segment of a line that passes through the selected specific location in space;

d. instructing the subject to position his head so that he sees the first reflected image of his eye at the particular spot in the first mirror and also sees the second reflected image of his eye at the particular spot in the second mirror.

14. The method of claim 13 also comprising placing a target on at least one of the mirrors which defines the particular spot on the at least one mirror where at least a portion of one of the reflected images is desired to be positioned.

15. The method of claim 13 also comprising placing a luminous indicator in at least one of the mirrors which defines the particular spot where at least a portion of one of the reflected images is desired to be positioned.

16. The method of claim 13 wherein at least one of the mirrors has a concave surface for magnification of one of the reflected images.

17. The method of claim 13 wherein the camera detects infrared light.

18. The method of claim 17 wherein at least one of the mirrors is a cold mirror and the camera is positioned to receive infrared light reflected from the eye of the subject that passes through the cold mirror.

19. The method of claim 13 wherein at least one of the mirrors is a partially-transparent mirror and the camera is positioned to receive light reflected from the eye of the subject that passes through the at least one of the mirrors.

20. The method of claim 13 also comprising the step of detecting a specular reflection of the light beam from at least one eye of the subject or from at least one lens of eyeglasses worn by the subject.

21. The method of claim 20 wherein the specular reflection is detected by a photodetector.

22. The method of claim 20 wherein the specular reflection is detected by the camera.

23. The method of claim 20 also comprising the step of producing an audible tone when the specular reflection is detected.

24. The method of claim 20 also comprising the step of activating a luminous indicator when the specular reflection is detected.

25. A method of aiming at and focusing on an eye of a subject to be photographed by a camera having a manual focus mechanism comprising the steps of:

a. providing a mirror such that the subject can see a reflected image of his eye at a particular spot in the mirror only when his line of sight is in the field of view of the camera;

b. directing a collimated light beam in synchronization with the manual focus mechanism of the camera such that the eye of the subject can see the beam only when the eye is at a distance of clear focus on the line of sight established in step a; and

d. instructing the subject to position his head so that he sees the reflected image of his eye at the particular spot in the mirror and then manually adjust the focus of the camera until he sees the collimated light beam.

26. The method of claim 25 also comprising placing a target on the mirror which defines a particular spot where at least a portion of the reflected image is desired to be positioned.

27. The method of claim 25 also comprising placing a luminous indicator in the mirror which defines the particular spot where at least a portion of a reflected image is desired to be positioned.

28. The method of claim 25 wherein the mirror has a concave surface for magnification of the reflected image.

29. The method of claim 25 wherein the camera detects infrared light.

30. The method of claim 29 wherein the mirror is a cold mirror and the camera is positioned to receive infrared light reflected from the eye of the subject that passes through the mirror.

31. The method of claim 25 wherein the mirror is a partially-transparent mirror and the camera is positioned to receive light reflected from the eye of the subject that passes through the mirror.

32. The method of claim 25 also comprising the step of detecting a specular reflection of the light beam from at least one eye of the subject or from at least one lens of eyeglasses worn by the subject.

33. The method of claim 32 wherein the specular reflection is detected by a photodetector.

34. The method of claim 32 wherein the specular reflection is detected by the camera.

35. The method of claim 32 also comprising the step of producing an audible tone when the specular reflection is detected.

36. The method of claim 32 also comprising the step of activating a luminous indicator when the specular reflection is detected.

37. A method of positioning an eye of a subject to be photographed by a camera comprising the steps of:

a. selecting a specific location in space within a field of view of the camera at which an eye of the subject is desired to be positioned;

b. providing a mirror at a fixed distance from the selected specific location in space such that the subject can see a reflected image of his eye at a particular spot in the mirror only when his line of sight is a segment of a line that passes through the selected specific location in space;

c. directing a light sheet in a manner so that the light sheet passes through the selected specific location in space; and

d. instructing the subject to position his head so that he sees the reflected image of his eye at the particular spot in the mirror and also sees the light sheet.

38. The method of claim 37 also comprising placing a target on the mirror which defines the particular spot where at least a portion of a reflected image is desired to be positioned.

39. The method of claim 37 also comprising placing a luminous indicator in the mirror which defines a particular spot where at least a portion of a reflected image is desired to be positioned.

40. The method of claim 37 wherein the mirror has a concave surface for magnification of a reflected image.

41. The method of claim 37 wherein the camera detects infrared light.

42. The method of claim 41 wherein the mirror is a cold mirror and the camera is positioned to receive infrared light reflected from the eye of the subject that passes through the mirror.

43. The method of claim 37 wherein the mirror is a partially-transparent mirror and the camera is positioned to receive light reflected from the eye of the subject that passes through the mirror.

44. The method of claim 37 also comprising the step of detecting a specular reflection of the light sheet from at least one eye of the subject or from at least one lens of eyeglasses worn by the subject.

45. The method of claim 44 wherein the specular reflection is detected by a photodetector.

46. The method of claim 44 wherein the specular reflection is detected by the camera.

47. The method of claim 44 also comprising the step of producing an audible tone when the specular reflection is detected.

48. The method of claim 44 also comprising the step of activating a luminous indicator when the specular reflection is detected.

49. A system for taking an image of a subject comprised of:

a. a mirror positioned a fixed distance from a selected specific point in space to reflect light from a subject positioned at the selected specific point in space back to that selected specific point in space;

b. a collimated light source positioned to direct a light beam through the selected specific point in space in a manner so that an eye positioned at the selected specific point in space can see the light beam while the subject can see a reflected image of his eye at a particular spot in the mirror when his line of sight is a segment of a line that passes from the mirror through the specific point in space; and

c. a camera positioned so that the selected specific point in space is in the field of view of the camera.

50. The system of claim 49 also comprising a pedestal on which at least one of the camera, the mirror and the light source is mounted.

51. The system of claim 49 also comprising a secondary mirror positioned between the selected point and the mirror so that light reflected from a subject at the selected point will pass through the secondary mirror.

52. The system of claim 51 wherein the secondary mirror is a cold mirror.

53. The system of claim 51 wherein the secondary mirror is a hot mirror.

54. The system of claim 49 also comprising a target inscribed on the mirror which defines a particular spot where at least a portion of the reflected image is desired to be positioned.

55. The system of claim 49 also comprising a photodetector positioned to detect a specular reflection of the light beam from at least one eye of the subject or from a lens of eyeglasses worn by the subject.

56. The system of claim 55 also comprising a tone generator connected to the photodetector.

57. The system of claim 49 wherein the light source produces and the camera detects infrared light.

58. The system of claim 49 also comprising a luminous indicator attached to the mirror.

59. The system of claim 49 wherein the camera has a focal point at the selected specific location in space.

60. The system of claim 49 wherein the camera has a focus mechanism and the light source is connected to the focus mechanism in a manner so that movement of the focus mechanism moves the light source and the light source can only be seen by the eye when the eye is at the point at which the camera is focused.

61. A system for taking an image of a subject comprised of:

a. a mirror positioned a fixed distance from a selected specific point in space to reflect light from a subject positioned at the selected specific point in space back to that selected specific point in space;

b. a light source which produces a sheet of light positioned to direct the sheet of light through the selected specific point in space in a manner so that an eye positioned at the selected specific point in space can see the light while the subject can see a reflected image of his eye at a particular spot in the mirror when his line of sight is a segment of a line that passes from the mirror through the specific point in space; and

c. a camera positioned so that the selected specific point in space is in the field of view of the camera.

62. The system of claim 61 also comprising a pedestal on which at least one of the camera, the mirror and the light source is mounted.

63. The system of claim 61 also comprising a secondary mirror positioned between the selected point and the mirror so that light reflected from a subject at the selected point will pass through the secondary mirror.

64. The system of claim 63 wherein the secondary mirror is a cold mirror.

65. The system of claim 63 wherein the secondary mirror is a hot mirror.

66. The system of claim 61 also comprising a target inscribed on the mirror which defines a particular spot where at least a portion of a reflected image is desired to be positioned.

67. The system of claim 61 also comprising a photodetector positioned to detect a specular reflection of light from at least one eye of the subject or from a lens of eyeglasses worn by the subject.

68. The system of claim 67 also comprising a tone generator connected to the photodetector.

69. The system of claim 61 wherein the light source produces and the camera detects infrared light.

70. The system of claim 61 also comprising a luminous indicator attached to the mirror.

71. The system of claim 61 wherein the camera has a focal point at the selected specific location in space.

72. The system of claim 61 wherein the camera has a focus mechanism and the light source is connected to the focus mechanism in a manner so that movement of the focus mechanism moves the light source and the light source can only be seen by the eye when the eye is at a focal point of the camera.