Dynamically variable machine readable binary code and method for reading and producing thereof

• US 5,477,045 A
• Filed: 06/23/1994
• Issued: 12/19/1995
• Est. Priority Date: 05/05/1988
• Status: Expired due to Term

• Current Assignee: Microscan Systems Inc (Omron Corporation)
• Original Assignee: International Data Matrix Incorporated
• Inventors: Priddy, Dennis G., Cymbalski, Robert S.
• Primary Examiner(s): Hajec, Donald
• Assistant Examiner(s): Le, Thien Minh
• Application Number:
  US08/264,856
• Time in Patent Office: 544 Days
• Field of Search: 235/436, 235/456, 235/494, 235/437, 235/432, 235/470, 380/55, 369/180, 371/43, 341/95
• US Class Current: 235/494
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 2019/06262 with target- or other orientation-indicating feature
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence

Abstract

A machine readable binary code which is dynamically variable in size, format and density of information is provided. The binary code is formed as a matrix having a perimeter and data contained therein. The perimeter is provided with density indicia for indicating the density of data contained within the matrix. The perimeter is also provided with size indicia for indicating the size of the matrix. By utilizing the density indicia and size indicia, a scanning device is able to calculate the size and information density of the binary code.

Claims

1. An apparatus for reading a dynamically variable machine optically readable code, said code comprising data formed as a plurality of data elements forming a two dimensional array and having a perimeter, said code having a variable number of data elements and including a density indicia for determining the density of data elements contained within the code, said density indicia being disposed in said code independently of the positioning of said data elements comprising said data, said density indicia being a function of the number of data elements comprising data in said code and said apparatus operating on said density indicia to determine the density of data contained within said code.

2. The apparatus of claim 1 wherein the density indicia is formed of a first pattern and a second pattern, each pattern having a number of data elements having distinguishable values, wherein the product of the number of data elements in the first pattern and the number of data elements in the second pattern identifies the density of data.

3. The apparatus of claim 2 wherein the first and second patterns further comprise two lines of data elements each having alternating light area and dark area data elements.

4. The apparatus of claim 3 wherein the two lines are disposed in the code perimeter and intersect at a corner of the perimeter.

5. The apparatus of claim 4 wherein the two lines have identical alternating light area and dark area patterns.

6. The apparatus of claim 5 further comprising means for optically scanning a visual field capable of containing said code and determining therefrom the density indicia.

7. The apparatus of claim 6 wherein the optically scanning means further comprises a source of radiation directed to illuminate the visual field, wherein the optically scanning means detects radiation reflected from the visual field in response to the illuminating radiation.

8. The apparatus of claim 7 wherein the optically scanning means further comprises a laser reader having a source of laser radiation and means for illuminating the visual field with the laser radiation.

9. The apparatus of claim 6 wherein the optically scanning means further comprises a light sensitive electronic array.

10. The apparatus of claim 9 wherein the light sensitive electronic array further comprises a light sensitive area array and a lens to focus an image of the visual field onto the area array, wherein a two-dimensional image is captured by the area array.

11. The apparatus of claim 10 wherein the light sensitive area array and lens further comprise an optical CCD camera.

12. The apparatus of claim 9 wherein the light sensitive array further comprises a light sensitive linear array, wherein a two-dimensional image is captured in response to the linear array being moved across the visual field.

13. The apparatus of claim 7 wherein the optically scanning means further comprises a light sensitive electronic array.

14. The apparatus of claim 13 wherein the light sensitive electronic array further comprises a light sensitive area array and a lens to focus an image of the visual field onto the area array, wherein a two-dimensional image is captured by the area array.

15. The apparatus of claim 14 wherein the light sensitive area array and lens further comprise an optical CCD camera.

16. The apparatus of claim 13 wherein the light sensitive array further comprises a light sensitive linear array, wherein a two-dimensional image is captured in response to the linear array being moved across the visual field.

17. The apparatus of claim 1 wherein the perimeter of the code further comprises a size indicia for determining the physical size of the code and said apparatus operates on said size indicia to determine the physical size of the code.

18. The apparatus of claim 17 wherein said binary code further comprises an orientation indicia and said apparatus operates on said orientation indicia to determine the orientation of the code relative to a visual field in which said matrix is disposed.

19. The apparatus of claim 17 wherein said binary code further comprises an indicia indicating the distribution pattern of the data within the code, and said apparatus operates on said indicia to determine the distribution of data within the code.

20. The apparatus of claim 17 wherein the size indicia further comprises a first side of the perimeter and a second side of the perimeter, the first and second sides being solid lines and intersecting at a first corner.

21. The apparatus of claim 20 wherein the density indicia further comprises a third side and a fourth side of the perimeter intersecting at a second corner, each of the third and fourth sides being formed of a pattern of alternating light area and dark area data elements, wherein the operating means further comprises means for counting the number of alternating light areas and dark areas in the third and fourth sides and calculating therefrom a product corresponding to the number of data elements comprising data in the code.

22. The apparatus of claim 21 wherein the code further comprises data arranged in a predetermined pattern and a pattern distribution key identifying the predetermined pattern, said operating means further comprising means for identifying the pattern distribution key in said code, and means for decoding the data elements of the code using said pattern distribution key.

23. An apparatus for reading a machine optically readable code, said code comprising data formed as a plurality of data elements having a perimeter, the perimeter including a size indicia as a first side of the perimeter and a second side of the perimeter, said first side and second side each being formed of a solid line, the first side and second side intersecting at a first corner and corresponding to the orientation of the code relative to a visual field within which said code is disposed, said apparatus having means for reading said code and means for operating on said size indicia and determining the physical size of the code and the distortion of the code.

24. The apparatus of claim 23 wherein the code further comprises a density indicia for determining the density of data contained within the code, said density indicia being disposed in said code independently of the positioning of said data elements comprising data, said density indicia being a function of the number of data elements comprising data in said code and said apparatus operating on said density indicia to determine the density of data contained within said code.

25. The apparatus of claim 24 wherein the density indicia is formed of two patterns of data elements not comprising data, each pattern having a number of data elements that are optically distinguishable, wherein the product of the number of data elements in the two patterns identifies the density of data.

26. The apparatus of claim 25 wherein said two patterns further comprises two lines of data elements.

27. The apparatus of claim 26 wherein said two lines of the density indicia are disposed in the perimeter and intersect at a corner of the perimeter.

28. The apparatus of claim 26 wherein the means for reading the code further comprises means for optically scanning a visual field capable of containing a code and determining therefrom the orientation indicia.

29. The apparatus of claim 28 wherein the optically scanning means further comprises a source of radiation directed to illuminate the visual field, wherein the optically scanning means detects radiation reflected from the visual field in response to the illuminating radiation.

30. The apparatus of claim 29 wherein the optically scanning means further comprises a laser reader having a source of laser radiation and means for illuminating the visual field with the laser radiation.

31. The apparatus of claim 28 wherein the optically scanning means further comprises a light sensitive electronic array.

32. The apparatus of claim 31 wherein the light sensitive electronic array further comprises a light sensitive area array and a lens to focus an image of the visual field onto the area array, wherein a two-dimensional image is captured by the area array.

33. The apparatus of claim 32 wherein the light sensitive area array and lens further comprise an optical CCD camera.

34. The apparatus of claim 31 wherein the light sensitive array further comprises a light sensitive array, wherein a two-dimensional image is captured in response to the linear array being moved across the visual field.

35. The apparatus of claim 29 wherein the optically scanning means further comprises a light sensitive electronic array.

36. The apparatus of claim 35 wherein the light sensitive electronic array further comprises a light sensitive area array and a lens to focus an image of the visual field onto the area array, wherein a two-dimensional image is captured by the area array.

37. The apparatus of claim 36 wherein the light sensitive area array and lens further comprise an optical CCD camera.

38. The apparatus of claim 35 wherein the light sensitive array further comprises a light sensitive linear array, wherein a two-dimensional image is captured in response to the linear array being moved across the visual field.

39. An apparatus for reading a machine optically readable code disposed within a visual field, said code comprising data formed as a plurality of data elements having a perimeter and a size indicia indicating the physical size of the code, the apparatus operating on the size indicia to determine the physical size of the code, the code further including an orientation indicia, the apparatus further operating on the orientation indicia to determine the orientation of the code relative to a visual field in which the code is disposed, the orientation indicia including a first side of the perimeter, a second side of the perimeter, said first and second sides each being formed of a solid line, the first side and second side intersecting a first angle, said first angle defining the orientation of the matrix.

40. The apparatus of claim 39 wherein the first and second sides form a corner of the code perimeter.

41. The apparatus of claim 40 wherein the first and second sides are of equal length.

42. The apparatus of claim 40 wherein the size indicia is disposed in the perimeter of the code.

43. The apparatus of claim 42 wherein the size indicia and the orientation indicia comprise the same first and second solid lines.

44. The apparatus of claim 43 wherein the means sensor scanning means further comprising means for optically scanning a visual field capable of containing a code and determining therefrom the size indicia.

45. The apparatus of claim 44 wherein the optically scanning means further comprises a source of radiation directed to illuminate the visual field, wherein the optically scanning means detects radiation reflected from the visual field in response to the illuminating radiation.

46. The apparatus of claim 45 wherein the optically scanning means further comprises a laser reader having a source of laser radiation and means for illuminating the visual field with the laser radiation.

47. The apparatus of claim 44 wherein the optically scanning means further comprises a light sensitive electronic array.

48. The apparatus of claim 47 wherein the light sensitive electronic array further comprises a light sensitive area array and a len to focus an image of the visual field onto the area array, wherein a two-dimensional image is captured by the area array.

49. The apparatus of claim 48 wherein the light sensitive area array and lens further comprise an optical CCD camera.

50. The apparatus of claim 47 wherein the light sensitive array further comprises a light sensitive linear array, wherein a two-dimensional image is captured in response to the linear array being moved across the visual field.

51. The apparatus of claim 45 wherein the optically scanning means further comprises a light sensitive electronic array.

52. The apparatus of claim 51 wherein the light sensitive electronic array further comprises a light sensitive area array and a lens to focus an image of the visual field onto the area array, wherein a two-dimensional image is captured by the area array.

53. The apparatus of claim 52 wherein the light sensitive area array and lens further comprise an optical CCD camera.

54. The apparatus of claim 51 wherein the light sensitive array further comprises a light sensitive linear array, wherein a two-dimensional image is captured in response to the linear array being moved across the visual field.

55. A method for determining the density of a dynamically variable machine readable optical symbol having a code formed of a plurality of data elements in a two dimensional array representing coded data and a perimeter including a first side and a second side, the first and second sides forming a density indicia as first and second patterns having alternating light and dark areas, the first side and second side intersecting at a first corner, the product of the number of alternating light and dark areas of the first and second sides corresponding to the density of coded data in the matrix, comprising the steps of:

scanning the symbol with an optical scanner and converting the scanned image to a bit map representative of the scanned symbol;

processing the bit-map and determining therefrom the number of alternating light and dark areas in the first and second sides respectively; and

determining the product of the number of alternating cells of the first and second sides as the density of data in the code.

56. The method of claim 55 wherein the scanning step further comprises providing a light sensitive device, detecting radiation reflected from a visual field containing the code, forming a two-dimensional electronic representation of the visual field in response to the detected reflected radiation, and forming a bit map from the two-dimensional representation.

57. The method of claim 56 wherein the step of detecting radiation further comprises illuminating the visual field with radiation, wherein the detected reflected radiation is responsive to the illuminating radiation.

58. The method of claim 56 wherein the step of detecting radiation further comprises generating laser radiation, illuminating the visual field with said laser radiation, and detecting the radiation reflected in response to the laser radiation.

59. The method of claim 56 wherein the step of detecting radiation further comprises providing a light sensitive electronic array and capturing electronic data corresponding to a two-dimensional image of the visual field.

60. The method of claim 59 wherein the step of providing a light sensitive array further comprises providing light sensitive area array and a lens, focussing an image of the visual field on the area array, and capturing a two-dimensional electronic representation of the scanned visual field.

61. The method of claim 60 wherein providing a light sensitive area array and a lens further comprises providing an optical CCD camera.

62. The method of claims 59 wherein the step of providing a light sensitive array further comprises providing a linear array, and moving the linear array across the visual field and capturing a two-dimensional electronic representation of the visual field in response to said movement.

63. The method of claim 57 wherein the step of detecting radiation further comprises providing a light sensitive electronic array and capturing electronic data corresponding to a two-dimensional image of the visual field.

64. The method of claim 63 wherein the step of providing a light sensitive array further comprises providing light sensitive area array and a lens, focussing an image of the visual field on the area array, and capturing a two-dimensional electronic representation of the scanned visual field.

65. The method of claim 64 wherein providing a light sensitive area array and a lens further comprises providing an optical CCD camera.

66. The method of claim 63 wherein the step of providing a light sensitive array further comprises providing a linear array, and moving the linear array across the visual field and capturing a two-dimensional electronic representation of the visual field in response to said movement.

67. A method for determining the size of a dynamically variably machine optically readable symbol having a code formed of a plurality of data elements in a two dimensional array representing coded data and a perimeter having a first side and a second side, the first side and second side each being formed of a solid line and intersecting at a first corner, and determining the location of each data element of data of the symbol comprising:

scanning the symbol with an optical scanner and converting the scanned image to a bit map representative of the scanned image of the symbol;

processing the bit map and determining the length of the first and second sides and the angle formed between the first and second sides; and

determining the location of each data element of coded data in the code by compensating for any linear distortion based on the determined angle.

68. The method of claim 67 wherein determining the location of each data element further comprises determining the physical center of each data element.

69. The method of claim 67 wherein the scanning step further comprises providing a light sensitive device, detecting radiation reflected from a visual field containing the code, forming a two-dimensional electronic representation of the visual field in response to the detected reflected radiation, and forming the bit map from the two-dimensional electronic representation.

70. The method of claim 69 wherein the step of detecting radiation further comprises illuminating the visual field with radiation, wherein the detected reflected radiation is responsive to the illuminating radiation.

71. The method of claim 69 wherein the step of detecting radiation further comprises generating laser radiation, illuminating the visual field with said laser radiation, and detecting the radiation reflected in response to the laser radiation.

72. The method of claim 68 wherein the step of detecting radiation further comprises providing a light sensitive electronic array and capturing electronic data corresponding to a two-dimensional image of the visual field.

73. The method of claim 72 wherein the step of providing a light sensitive array further comprises providing light sensitive area array and a lens, focussing an image of the visual field on the area array, and capturing a two-dimensional electronic representation of the scanned visual field.

74. The method of claim 73 wherein providing a light sensitive area array and a lens further comprises providing an optical CCD camera.

75. The method of claim 72 wherein the step of providing a light sensitive array further comprises providing a linear array, and moving the linear array across the visual field and capturing a two-dimensional electronic representation of the visual field in response to said movement.

76. The method of claim 70 wherein the step of detecting radiation further comprises providing a light sensitive electronic array and capturing electronic data corresponding to a two-dimensional image of the visual field.

77. The method of claim 76 wherein the step of providing a light sensitive array further comprises providing light sensitive area array and a lens, focussing an image of the visual field on the area array, and capturing a two-dimensional electronic representation of the scanned visual field.

78. The method of claim 77 wherein providing a light sensitive area array and a lens further comprises providing an optical CCD camera.

79. The method of claim 76 wherein the step of providing a light sensitive array further comprises providing a linear array, and moving the linear array across the visual field and capturing a two-dimensional electronic representation of the visual field in response to said movement.