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

• US 5,479,004 A
• Filed: 06/23/1994
• Issued: 12/26/1995
• 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:
  US08/264,790
• Time in Patent Office: 551 Days
• Field of Search: 235/436, 235/456, 235/494, 235/437, 235/432, 235/470, 380/55, 369/100, 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. Apparatus for reading a machine readable code having a perimeter and containing a plurality of data elements in a two-dimensional spatial array representing coded information, comprising:

means for sensor scanning a visual field to capture a two-dimensional image of the visual field;

means for converting a scanned visual field image into a bit map representing the scanned visual field;

first processing means for processing the bit map to locate and determine a size indicia in the bit map, the size indicia indicating the size of the code and comprising a first solid line and a second solid line, the first and second solid lines intersecting at a first corner and forming a portion of the code perimeter;

second processing means for processing the bit map, in response to locating the size indicia, to locate and determine a density indicia in the bitmap, the density indicia comprising a first pattern of alternating light areas and dark areas and a second pattern of alternating light areas and dark areas, the first and second patterns intersecting at a second corner and forming another portion of the code perimeter, the product of the numbers of alternating light areas and dark areas in the first and second patterns indicating the number of data elements in the code representing coded information; and

third processing means responsive to the determined size indicia and density indicia, for processing the bitmap and determining the coded information in the plurality of data elements.

2. The apparatus of claim 1 wherein the sensor scanning means further comprises means for optically scanning a visual field.

3. The apparatus of claim 2 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.

4. The apparatus of claim 3 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.

5. The apparatus of claim 2 wherein the optically scanning means further comprises a light sensitive electronic array.

6. The apparatus of claim 5 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.

7. The apparatus of claim 6 wherein the light sensitive area array and lens further comprise an optical CCD camera.

8. The apparatus of claim 5 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.

9. The apparatus of claim 3 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. A method for scanning a machine readable code having a perimeter and containing a plurality of data elements in a two-dimensional spatial array representing coded information comprising:

scanning a visual field and capturing a two-dimensional image of the visual field;

converting a captured visual field image into a bit map representing the scanned visual field;

processing the bit map to locate and determine a size indicia in the bit map, the size indicia indicating the size of the code and comprising a first solid line and a second solid line, the first and second solid lines intersecting at a first corner and forming a portion of a perimeter of the code the size indicia;

further processing the bit map, in response to locating the size indicia, to locate and determine a density indicia in the bitmap, the density indicia comprising a first pattern of alternating light areas and dark areas and a second pattern of alternating light areas and dark areas, the first and second patterns intersecting at a second corner and forming another portion of the perimeter of the code, the product of the numbers of alternating light areas and dark areas in the first and second patterns indicating the number of data elements in the code representing coded information; and

determining the coded information in the plurality of data elements in response to the determined size indicia and density indicia and the bitmap.

14. The method of claim 13 wherein the scanning step further comprises providing a light sensitive device, detecting radiation reflected from a visual field containing the code, and forming a two-dimensional electronic representation of the visual field in response to the detected reflected radiation.

15. The method of claim 14 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.

16. The method of claim 14 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.

17. The method of claim 14 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.

18. The method of claim 17 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.

19. The method of claim 18 wherein providing a light sensitive area array and a lens further comprises providing an optical CCD camera.

20. The method of claim 18 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.

21. The method of claim 15 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.

22. The method of claim 21 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.

23. The method of claim 22 wherein providing a light sensitive area array and a lens further comprises providing an optical CCD camera.

24. The method of claim 21 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.