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

• US 20030121978A1
• Filed: 12/09/2002
• Published: 07/03/2003
• Est. Priority Date: 07/14/2000
• Status: Active Grant

• Current Assignee: PatientSafe Solutions, Inc. (Stryker Corporation)
• Original Assignee: Intellidot Corporation (Stryker Corporation)
• Inventors: Blei, Keith, Rubin, Kim T., Haggis, John R.
• Granted Patent: US 6,830,197 B2
• Time in Patent Office: Days
• US Class Current: 235/462.1
• 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 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.

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 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.

9. The code of claim 8, 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.

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.

15. The code of claim 12, wherein 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 defined shape 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 target perimeters are not aligned with said regular grid.

100. The method of claim 88 wherein said coded information is said code of claim 1.

19. 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 the 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.

20. The code of claim 19, wherein the 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.

21. The code of claim 19, 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.

22. The code of claim 19, 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.

23. The code of claim 19, 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.

24. The code of claim 19, wherein a portion of said target is embedded in said plurality of data cells.

25. The code of claim 19, wherein a portion of said target has n-fold radial symmetry, where n is equal to three.

26. The code of claim 19, 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.

101. The method of claim 88 wherein said coded information is said code of claim 19.

27. 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 the 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.

28. The code of claim 27, 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.

29. The code of claim 27, wherein said boundary of individual ones of said plurality of data cells adjoins at least some of the interior of said enclosed curvilinear shape that is not one of said plurality of data cells.

30. The code of claim 27, wherein said plurality of data cells are arranged on a hexagonal grid.

31. The code of claim 27, wherein said plurality of data cells are arranged in two or more contiguous groups.

32. The code of claim 27, wherein said enclosed curvilinear shape is an ellipse.

33. The code of claim 27, wherein said target is embedded in said plurality of data cells.

34. The code of claim 27, 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.

35. The code of claim 27, wherein said target has a target centroid, wherein said enclosed curvilinear shape is an ellipse having a code centroid, wherein said centroid offset is the 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.

102. The method of claim 88 wherein said coded information is said code of claim 27.

36. 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.

37. The code of claim 36, 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.

103. The method of claim 88 wherein said coded information is said code of claim 36.

38. 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.

39. The code of claim 38, wherein said target includes a distinctive symbol, where said distinctive symbol indicates the orientation of said code.

40. The code of claim 39, wherein said portion of said target is a trademark.

41. The code of claim 38, 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.

104. The method of claim 88 wherein said coded information is said code of claim 38.

42. 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 the 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.

43. The code of claim 42, wherein said enclosed curvilinear shape is an ellipse.

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

45. The code of claim 42, 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.

46. The code of claim 42, wherein said enclosed curvilinear shape is a circle.

47. The code of claim 42, 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.

48. The code of claim 42, wherein said plurality of data cells are arranged on a hexagonal grid.

49. The code of claim 42, wherein said target has n-fold radial symmetry, where n is equal to three.

50. The code of claim 42, wherein said plurality of data cells are arranged in two or more contiguous groups.

105. The method of claim 88 wherein said coded information is said code of claim 42.

51. 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

52. The code of claim 51, 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 the purpose of decreasing the number of individual ones of said plurality of data cells that adjoin data cells belonging to a different symbol.

53. The code of claim 51, 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.

54. The code of claim 51, 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.

55. The code of claim 51, wherein each of said plurality of data cells within one of said two or more symbols has a ratio given by the 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.

106. The method of claim 88 wherein said coded information is said code of claim 51.

56. A method for the storing of 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 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 predetermined shape and optical properties relative to said code pattern,

where said target includes a portion proximate to said periphery, where said target has approximately radial features distinct from said plurality of data cells, and where the centroid of said target is adjacent to the centroid of said enclosed code area.

57. The method of claim 56, wherein a preferred rotational orientation of said code pattern is not evident.

58. The method of claim 56, wherein applying said code pattern and applying said target are accomplished in one operation.

59. The method of claim 56, wherein said converting includes encrypting said information.

60. The method of claim 56, wherein said converting includes the use of an error correction algorithm.

61. The method of claim 56, further comprising applying a quality pattern having predetermined shapes and optical properties relative to said code pattern.

62. The method of claim 56, wherein the distance between any two points of said target is within 15% of the distance between corresponding points of said predetermined target.

63. The method of claim 56, 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.

64. The method of claim 63, wherein said converting includes use of an error correction algorithm, such that said information is stored in less than the total number of said plurality of data cells.

65. The method of claim 64, 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.

66. A method of obtaining information content from a two-dimensional optical pattern, comprising:

capturing an image of said optical pattern, where said image is contained within an enclosed shape having a periphery;

ascertaining locations in two dimensions of a plurality of optical target elements positioned within said pattern image, where each optical target element has a predetermined shape and position within said pattern image, where at least one of said plurality of optical target elements has distinct, approximately radial features, and where a portion of said plurality of optical target elements is proximate to said periphery;

locating optical cells that are spaced apart from each other at predetermined locations in the optical pattern image with respect to the ascertained optical target elements and which lie primarily within a boundary formed by the ascertained target elements; and

determining the information content of at least some of said located optical cells.

67. The method of claim 66, wherein said optical pattern has no evident preferred rotational orientation.

68. The method of claim 66, wherein said information content includes a first information content and a second information content, and wherein said determining comprising determining said first information content at a first location, and determining said second information content at a second location.

69. The method of claim 66, wherein said determining said information content includes encrypting said information.

70. The method of claim 66, wherein said target has a target centroid, wherein said enclosed shape has a shape centroid, and wherein said target centroid is adjacent to said shape centroid.

71. The method of claim 66, wherein said plurality of optical cells are substantially contained within said enclosed shape, and wherein said plurality of data cells embeds and is distinct from a portion of said target.

72. The method of claim 66, wherein said plurality of optical cells are arranged in three, noncontiguous clusters.

73. The method of claim 66, wherein the distance between any two points of said target is within 15% of the distance between corresponding points of said predetermined target.

74. The method of claim 66, wherein said imaging of said plurality of optical cells and said imaging of said target are acquired at the same time.

75. The method of claim 66, wherein said generating includes an error correction algorithm, such that said information is stored in less than the total number of said plurality of optical cells.

76. The method of claim 66, wherein said information content is a number, and wherein said determining comprises:

ascertaining the optical properties of at least one of said plurality of optical cells;

generating a number according to the optical properties and location of said located optical cells; and

decoding the generated number.

77. The method of claim 76, wherein said plurality of optical cells is 114 optical cells, wherein said generated number is a 114-bit number, and said decoding comprising:

decoding said 114-bit number with a Reed-Solomon (19,11) algorithm to obtain a 66-bit number; and

selecting 64 bits of said 66-bit number, where said 64 bits are 64 pre-selected individual binary digits from said 66-bit number.

78. The method of claim 66, 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 optical cells corresponds to one place in a binary number.

79. The method of claim 78, wherein said imaging comprises:

acquiring said code image in a portable finder, where said finder comprises a memory and a wireless transmitter;

storing information related to said decoded binary number in said memory; and

transmitting, using said wireless transmitter, information related to said decoded binary number from said finder to another electronic device.

80. The method of claim 78, further comprising:

locating one or more quality control cells that are spaced apart from each other at predetermined locations in the optical pattern image;

imaging one or more of said quality control cells; and

transmitting, using said wireless transmitter, information regarding said image of one or more of said quality control cells, wherein said quality control cell image information is used to determine the code quality.

81. The method of claim 78, further comprising:

transmitting, using said wireless transmitter, information regarding the information content of at least some of said located optical cells, to a remote site; and

determining the information content of at least some of said located optical cells at said remote site.

87. The method claim 66 using the finder of claim 82.

82. A portable finder for contact decoding, said finder comprising:

a front surface;

imaging optics having a focal area located at or adjacent to said front surface;

a contact switch positioned to signal said finder that an object is located at or near said focal area;

a fight source illuminating the focus of said imaging optics;

imaging electronics to acquire an image of said focal area;

image processing electronics for acquiring a code image and converting said code image into transmittable information; and

telecommunications means for transmitting said information.

83. The finder of claim 82, further comprising a transparent nosepiece, where a first end of said transparent nosepiece is located near said front surface, where a second end of said transparent nosepiece is located near said imaging optics.

84. The finder of claim 82, further comprising a second item selected from a group consisting of a pager, a cellular telephone, a wireless telephone, a personal digital assistant, an electronic organizer, a calculator, a pen, a toy, a computer mouse, a credit card, a debit card, an automated teller machine card, and any combination thereof.

85. The finder of claim 83, further comprising a finder case for enclosing said imaging optics, a portion of said contact switch, said transparent nosepiece, said imaging electronics, said image processing electronics, and a portion of said telecommunications means.

86. The finder of claim 82, where said code is a two-dimensional code.

88. A method for acquiring coded information on a surface, where said acquiring is performed by a user with a finder, where said finder is hand-held by said user, said method comprising:

contacting said surface with said finder; and

notifying said user of said acquisition of said coded information.

89. The method of claim 88, said contacting further comprising:

activating acquisition electronics; and

converting said coded information into a digital code.

90. The method of claim 88, wherein said notifying said users notifies said user of said contacting.

91. The method of claim 90, wherein said finder includes a switch, wherein said contacting said surface includes toggling said switch, and wherein said notifying said user includes the tactile sensation of toggling said switch.

92. The method of claim 90, wherein said finder includes a switch, wherein said contacting said surface includes toggling said switch, and wherein said notifying said user includes the audible sensation of toggling said switch.

93. The method of claim 90, wherein said finder includes an light source, wherein said contacting said surface includes varying the intensity of said light source, and wherein said notifying said user includes variations in the intensity of the light source.

94. The method of claim 93, wherein said light source illuminates said surface.

95. The method of claim 93, wherein said light source is a notification light.

96. The method of claim 89, said notifying said user further comprising notifying said user of converting.

97. The method of claim 96, wherein said finder includes a light source, and wherein said notifying said user includes varying the intensity of said light source.

98. The method of claim 96, wherein said finder includes a noise source, and wherein said notifying said user includes varying the intensity of said noise source.

99. The method of claim 88, wherein said finder includes second item selected from a group consisting of a pager, a cellular telephone, a wireless telephone, a personal digital assistant, an electronic organizer, a calculator, a pen, a toy, a computer mouse, a credit card, a debit card, an automated teller machine card, and any combination thereof.