Compact matrix code and one-touch device and method for code reading

• US 6,601,772 B1
• Filed: 07/14/2000
• Issued: 08/05/2003
• Est. Priority Date: 07/14/2000
• Status: Expired due to Term

• Current Assignee: PatientSafe Solutions, Inc. (Stryker Corporation)
• Original Assignee: Intellidot Corporation (Stryker Corporation)
• Inventors: Haggis, John R., Blei, Keith, Rubin, Kim T.
• Primary Examiner(s): Le, Thien M.
• Assistant Examiner(s): TRAIL, ALLYSON NEEL
• Application Number:
  US09/616,265
• Time in Patent Office: 1,117 Days
• Field of Search: 235/494, 235/454, 235/456, 235/462.02, 235/375, 235/462.01, 235/380, 235/487, 235/472.01
• US Class Current: 235/494
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/1417 2D bar codes
• CPC Class Codes: G06K 7/1443 locating of the code in an image

Abstract

A two-dimensional matrix code, method of producing the code and a method and device for reading the code are presented. The code is a round, compact and distinct code that stores an error-corrected 64-bit number, embedded targets, and quality control information within a space small enough for imaging using a compact, hand-held code finder. The code incorporates white space both between the data areas and targets for easy identification of the code and to aid in image processing, and within the data area to correct for errors that sometimes occur when printing using low-quality techniques. Additionally, the code includes features to correct for other printing errors, such as variations in printing press speed and intentional aspect ratio stretching to fill copy space. The code is thus robust enough to be incorporated within newsprint and is also easily imaged using specially constructed code finders. A code finder device and a method of using the finder for acquiring a code of the present invention is also presented. The finder is portable and easy to use, requiring no rotational orientation for correct acquisition. Several embodiments are described, in which the finder contains illumination and communications electronics and means to notify the user of correct operation of the finder.

Claims

1. A two-dimensional code, comprising a plurality of data cells adjoining one another over at least one two-dimensional area of a surface and that optically stores information on the surface, individual ones of said plurality of data cells having predetermined shapes and positions and having one of at least two optical properties, and wherein individual ones of said plurality of data cells do not adjoin any other of said plurality of data cells on all sides.

2. The code of claim 1, further comprising one or more quality cells that provide code quality information, individual ones of said one or more quality cells having predetermined shapes, positions and optical properties.

3. The code of claim 1, wherein said at least two optical properties is exactly two optical properties.

4. The code of claim 1, wherein said plurality of data cells are arranged in two or more contiguous groups.

5. The code of claim 1, wherein said shapes are hexagons.

6. The code of claim 1, wherein said positions are arranged on a regular grid.

7. The code of claim 6, wherein said regular grid is a hexagonal grid.

8. The code of claim 1, further comprising a plurality of target elements that provides reference positions relative to said plurality of data cells, wherein individual ones of said target elements have predetermined optical properties and positions relative to said predetermined position of said plurality of data cells, and wherein said plurality of target elements are confined within a perimeter, where said perimeter is the perimeter of a defined shape having the minimum area to confine said plurality of target elements.

10. The code of claim 8, wherein said plurality of data cells are substantially confined by said perimeter.

11. The code of claim 8, wherein said defined shape is a regular polygon.

12. The code of claim 8, wherein said defined shape is an ellipse.

13. The code of claim 12, wherein said ellipse is a circle.

14. The code of claim 13, wherein the combination of said plurality of data cells and said plurality of target elements form a code image, and wherein said code image has no evident rotational orientation.

9. A two-dimensional code, comprising:

a plurality of data cells that optically stores information on a surface, individual ones of said plurality of data cells having predetermined shapes and positions and having one of at least two optical properties, where individual ones of said plurality of data cells do not adjoin others of said plurality of data cells on all sides, and

a plurality of target elements that provides reference positions relative to said plurality of data cells, wherein individual ones of said target elements have predetermined optical properties and positions relative to said predetermined position of said plurality of data cells, wherein said plurality of target elements are confined within a perimeter, where said perimeter is the perimeter of a defined shape having the minimum area to confine said plurality of target elements, and wherein the distance between any two points of said plurality of target elements is within 15% of the predetermined shapes and positions of said plurality of target elements.

15. A two-dimensional code, comprising:

a plurality of data cells that optically stores information on a surface, individual ones of said plurality of data cells having predetermined shapes and positions and having one of at least two optical properties, where individual ones of said plurality of data cells do not adjoin others of said plurality of data cells on all sides,

a plurality of target elements that provides reference positions relative to said plurality of data cells, wherein individual ones of said target elements have predetermined optical properties and positions relative to said predetermined position of said plurality of data cells, wherein said plurality of target elements are confined within a perimeter, where said perimeter is the perimeter of an ellipse having the minimum area to confine said plurality of target elements, said plurality of target elements further comprising;

a plurality of first target elements substantially distinct from said plurality of data cells, such that said plurality of first target elements provide an indication of the approximate location of said plurality of data cells; and

a plurality of second target elements, where said second target provides an indication of the approximate locations of individual ones of said plurality of data cells.

16. The code of claim 15, wherein said plurality of second target elements are substantially positioned near said perimeter.

17. The code of claim 15, wherein said ellipse has a centroid, and wherein said plurality of first target elements have a substantially radial component extending approximately from said perimeter to approximately said centroid.

18. The code of claim 17, wherein said plurality of data cells are arranged on a regular grid, wherein individual ones of said first target elements have corresponding first target perimeters, and wherein a substantial portion of individual ones of said plurality of first perimeters are not aligned with said regular grid.

19. The code of claim 15, wherein said ellipse is a circle.

20. A two-dimensional code comprising:

a plurality of data cells that optically stores information, wherein said plurality of data cells individually have one of at least two optical properties and where said plurality of data cells are located on a regular grid and are confined within a periphery; and

a target having predetermined optical properties and boundaries relative to a position of said plurality of data cells, where at least a portion of said boundaries does not lie on said regular grid, where a portion of said target is in proximity to said periphery, and where a portion of said target has approximately radial features distinct from said plurality of data cells.

21. The code of claim 20, wherein a combination of said plurality of data cells and said target form a code image, and wherein a preferred rotational orientation of said code image is not evident.

22. The code of claim 20, further comprising one or more quality cells that provide code quality information, individual ones of said one or more quality cells having predetermined shapes, positions and optical properties.

23. The code of claim 20, wherein said target has a target centroid, wherein said plurality of data cells has a data centroid, and wherein said target centroid is adjacent to said data centroid.

24. The code of claim 20, wherein said plurality of data cells is arranged in two or more contiguous groups, and wherein each of said two or more contiguous groups is separated by a portion of said target.

25. The code of claim 20, wherein a portion of said target is embedded in said plurality of data cells.

26. The code of claim 20, wherein a portion of said target has n-fold radial symmetry, where n is equal to three.

27. The code of claim 20, wherein said target is a first target, and further comprising a second target for locating said plurality of data cells, said second target having predetermined optical properties and boundaries relative to the position of said plurality of data cells, where said second target is substantially near said periphery.

28. A two-dimensional code comprising:

a plurality of data cells that optically stores information, individual ones of said plurality of data cells having predetermined boundaries and having one of at least two optical properties; and

a target having predetermined optical properties and boundaries relative to a position of said plurality of data cells, where said target is confined within an enclosed curvilinear shape having a periphery,

where said plurality of data cells are substantially enclosed within said periphery, and where a portion of said target has approximately radial features distinct from said plurality of data cells.

29. The code of claim 28, further comprising one or more quality cells that provide code quality information, individual ones of said one or more quality cells having predetermined shapes, positions and optical properties.

30. The code of claim 28, wherein said boundary of individual ones of said plurality of data cells adjoins at least some of an interior of said enclosed curvilinear shape that is not one of said plurality of data cells.

31. The code of claim 28, wherein said plurality of data cells are arranged on a hexagonal grid.

32. The code of claim 28, wherein said plurality of data cells are arranged in two or more contiguous groups.

33. The code of claim 28, wherein said enclosed curvilinear shape is an ellipse.

34. The code of claim 28, wherein said target is embedded in said plurality of data cells.

35. The code of claim 28, wherein said target is a first target, and further comprising a second target for locating said plurality of data cells, said second target having predetermined optical properties and boundaries relative to said boundaries of said plurality of data cells, where said second target is substantially near said periphery.

36. The code of claim 28, wherein said target has a target centroid, wherein said enclosed curvilinear shape is an ellipse having a code centroid, wherein said centroid offset is a distance between said code centroid and said target centroid, and wherein said centroid offset is less than or equal to 20% of said ellipse minor diameter.

37. A two-dimensional code comprising:

a plurality of data cells that optically stores information, individual ones of said plurality of data cells having predetermined shapes and positions and having one of at least two optical properties; and

a target having predetermined optical properties, shapes, and positions relative to the position of said plurality of data cells, where a portion of said target has n-fold radial symmetry, where n is equal to three.

38. The code of claim 37, further comprising one or more quality cells that provide code quality information, individual ones of said one or more quality cells having predetermined shapes, positions and optical properties.

39. A two-dimensional code comprising:

a plurality of data cells that optically stores information, individual ones of said plurality of data cells having predetermined shapes and positions and having one of at least two optical properties; and

a target having predetermined optical properties, shapes, and positions relative to the position of said plurality of data cells, such that a portion of said target is distinct and the code is easily recognizable.

40. The code of claim 39, wherein said target includes a distinctive symbol, where said distinctive symbol indicates the orientation of said code.

41. The code of claim 40, wherein said portion of said target is a trademark.

42. The code of claim 39, further comprising one or more quality cells that provide code quality information, individual ones of said one or more quality cells having predetermined shapes, positions and optical properties.

43. A two-dimensional code comprising:

a plurality of data cells that optically stores information, individual ones of said plurality of data cells having predetermined shapes and locations and having one of at least two optical properties, and said plurality of data cells having a data centroid; and

a target having predetermined optical properties, shapes, and locations relative to a position of said plurality of data cells, said target enclosed within an enclosed curvilinear shape having a periphery and a target centroid, where a portion of said target has approximately radial features distinct from said plurality of data cells, where said target centroid is adjacent to said data centroid, and where said plurality of data cells are substantially enclosed within said periphery.

44. The code of claim 43, wherein said enclosed curvilinear shape is an ellipse.

45. The code of claim 43, wherein said ellipse has a major diameter and wherein a distance between said data centroid and said target centroid is less than or equal to 20% of said major diameter.

46. The code of claim 43, further comprising one or more quality cells that provide code quality information, individual ones of said one or more quality cells having predetermined shapes, positions and optical properties.

47. The code of claim 43, wherein said enclosed curvilinear shape is a circle.

48. The code of claim 43, wherein individual ones of said plurality of data cells has a boundary, and wherein each of said boundaries adjoins at least some of the interior of said enclosed curvilinear code shape that is not one of said plurality of data cells.

49. The code of claim 43, wherein said plurality of data cells are arranged on a hexagonal grid.

50. The code of claim 43, wherein said target has n-fold radial symmetry, where n is equal to three.

51. The code of claim 43, wherein said plurality of data cells are arranged in two or more contiguous groups.

52. A two-dimensional code comprising:

a plurality of data cells that optically stores information, individual ones of said plurality of data cells having predetermined shapes and locations and having one of at least two optical properties; and

two or more symbols comprising equal numbers of said plurality of data cells, where said predetermined shapes and locations of said plurality of data cells are arranged such that adjoining data cells are more likely to belong to the same symbol than to a different symbol such that the code is tolerant of printing errors.

53. The code of claim 52, wherein said code further comprising background space that is not one of said plurality of data cells, and wherein at least some of said plurality of data cells are adjoined by background space for a purpose of decreasing a number of individual ones of said plurality of data cells that adjoin data cells belonging to a different symbol.

54. The code of claim 52, wherein each of said plurality of data cells within one of said two or more symbols has a number of adjoining data cells within the same symbol, and wherein said predetermined shapes and locations of said plurality of data cells are arranged to maximize said number.

55. The code of claim 52, wherein each of said plurality of data cells within one of said two or more symbols has a number of adjoining data cells within a different symbol, and wherein said predetermined shapes and locations of said plurality of data cells are arranged to minimize said number.

56. The code of claim 52, wherein each of said plurality of data cells within one of said two or more symbols has a ratio given by a number of adjoining data cells within the same symbol divided by the number of adjoining data cells within a different symbol, and wherein said predetermined shapes and locations of said plurality of data cells are arranged to maximize said number.

57. A method for storing information on a surface in a two-dimensional code comprising:

converting said information into a code pattern, said code pattern having two or more optical properties that spatially vary according to said information, and where said code pattern has predetermined shapes and locations, and is enclosed within a curvilinear code shape having a periphery;

applying said code pattern to said surface; and

applying a target for locating said code to said surface, said target comprising a predetermined shape and optical properties relative to said code pattern, wherein said target includes a portion proximate to said periphery, wherein said target has approximately radial features distinct from said plurality of data cells, and wherein a centroid of said target is adjacent to a centroid of said enclosed code area.

58. The method of claim 57, wherein a preferred rotational orientation of said code pattern is not evident.

59. The method of claim 57, wherein applying said code pattern and applying said target are accomplished in one operation.

60. The method of claim 57, wherein said converting includes encrypting said information.

61. The method of claim 57, wherein said converting includes the use of an error correction algorithm.

62. The method of claim 57, further comprising applying a quality pattern having predetermined shapes and optical properties relative to said code pattern.

63. The method of claim 57, wherein a distance between any two points of said target is within 15% of the distance between corresponding points of said predetermined target.

64. The method of claim 57, wherein said converting comprising converting said information into a binary number, wherein said code pattern comprising a plurality of data cells, individual ones of said plurality of data cells having predetermined shapes and locations within said code image, wherein said two or more optical properties is two optical properties, where each of said two optical properties corresponds to one of the two binary digits, and wherein each of said plurality of data cells corresponds to a bit of said binary number.

65. The method of claim 64, wherein said converting includes use of an error correction algorithm, such that said information is stored in less than a total number of said plurality of data cells.

66. The method of claim 65, wherein said information is a 64-bit number, wherein said converting converts said information into a 114-bit number, said error correction algorithm further comprising:

adding two additional binary digits to said 64-bit number to form a 66-bit number;

grouping said 66 bits into 11, 6-bit symbols; and

encoding said 11, 6-bit symbols with a Reed-Solomon (19,11) algorithm to obtain a 114-bit digit number.

67. An optical code formed on a surface of a substrate, comprising:

a perimeter defining an outer extent of the code,

at least one cluster within the perimeter of a plurality of data cells that adjoin one another in a two-dimensional pattern, individual ones of the plurality of data cells having a predetermined shape and one of at least first and second optical properties according to data being stored therein, and wherein none of the plurality of data cells having the first optical property are totally surrounded by others of the plurality of data cells having the same first optical property, and

a plurality of target elements within the perimeter and having one of said at least first and second optical properties, a fixed spatial relationship with said at least one cluster of a plurality of data cells and which contain no data.

68. The code of claim 67, wherein the substrate surface is of a first color, the first optical property is a second color that is optically distinguishable from the first color and the second optical property is the first color of the substrate surface.

69. The code of claim 68, wherein the plurality of target elements are of the second color.

70. The code of claim 69, wherein the second color is a dark color.

71. The code of claim 70, wherein the first color of the substrate surface is a light color.

72. The code of claim 67, wherein the predetermined shape of the data cells is a hexagon and the plurality of data cells adjoin one another by sharing edges of the hexagon shape.

73. The code of claim 67, wherein said perimeter is in the shape of an ellipse.

74. The code of claim 73, wherein the ellipse is a circle.

75. The code of claim 73, wherein the plurality of target elements include a plurality of areas that are elongated generally in a radial direction.

76. The code of claim 67, wherein said at least one cluster of a plurality of data cells includes exactly three clusters of such cells.

77. The code of claim 67, wherein the characteristic of none of the plurality of data cells having the first optical property being totally surrounded by others of the plurality of data cells having the same first optical property is accomplished by not using as data cells a plurality of non-cell areas within said at least one cluster that individually have said predetermined shape and said second optical property.

78. The code of claim 77, wherein said predetermined shape is a hexagon and the plurality of data cells and non-cell areas adjoin one another by sharing edges of the hexagon shape.

79. The code of claim 77, wherein said perimeter is in the shape of an ellipse.

80. The code of claim 79, wherein the ellipse is a circle.

81. The code of claim 77, wherein the plurality of target elements include a plurality of areas that are elongated generally in a radial direction.

82. An optical code formed on a surface of a substrate, comprising:

a perimeter defining an outer extent of the code,

a plurality of two-dimensional clusters of data cells spaced apart within the perimeter, the individual clusters including a plurality of hexagon shaped data cells adjoining one another, individual ones of the plurality of data cells either being printed or not-printed in accordance with a bit of data being stored therein, and wherein hexagon shaped areas within the clusters are not used as data cells so that none of the plurality of data cells that are printed can be surrounded by others of the plurality of data cells that are also printed, and

a plurality of target elements within the perimeter that are printed and have a fixed spatial relationship with the plurality of clusters of data cells.

83. The code of claim 82, wherein said perimeter is in the shape of an ellipse.

84. The code of claim 83, wherein the ellipse is a circle.

85. The code of claim 82, wherein the plurality of target elements include a plurality of areas that are elongated generally in a radial direction.

86. The code of claim 82, wherein said plurality of clusters of a plurality of data cells includes exactly three clusters of such cells.

87. The code of claim 84, wherein the plurality of target elements include a plurality of areas containing visible radially extending elements positioned to allow determination of a rotational orientation of the plurality clusters of data cells.

88. An optical code formed on a surface of a substrate, comprising:

a perimeter defining an outer extent of the code,

at least one cluster within the perimeter of a plurality of data cells that adjoin one another in a two-dimensional pattern, individual ones of the plurality of data cells having a predetermined shape and one of at least first and second optical properties according to at least one bit of data being stored therein,

wherein each of a plurality of data symbols adapted for use by a Forward Error Correction Algorithm are formed from a given number of bits of data encoded in order in a contiguous series of adjoining data cells, and

a plurality of target elements within the perimeter and having one of said at least first and second optical properties and a fixed spatial relationship with said at least one cluster of a plurality of data cells.

89. The code of claim 88, wherein said cluster additionally includes therein a plurality of non-data storage areas that individually have said predetermined shape.