Bar code symbology capable of encoding bytes, words, 16-bit characters, etc. and method and apparatus for printing and reading same

• US 6,186,406 B1
• Filed: 03/09/1999
• Issued: 02/13/2001
• Est. Priority Date: 11/05/1993
• Status: Expired due to Fees

• Current Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Original Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Inventors: Ackley, H. Sprague
• Primary Examiner(s): LE, THIEN MINH
• Application Number:
  US09/265,631
• Time in Patent Office: 707 Days
• Field of Search: 235/494, 235/439, 235/435, 235/462.01, 235/462.02, 235/462.03, 235/462.04, 235/462.05, 235/462.07, 235/462.08, 235/454, 235/472.01
• US Class Current: 235/494
• CPC Class Codes: G06K 1/121 by printing code marks applying code marks to labels B65C9/46; marking or coding completed packages B65B61/26
• CPC Class Codes: G06K 19/06028 using bar codes
• 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 new bar code symbology in an exemplary embodiment employs three bars (and spaces) within nine modules, similar to Code 93. Fifty-three data characters are defined, including several special mode characters. By employing these special mode characters, together with certain routines, three symbol characters can represent two 8-bit bytes, or one 16-bit word. As a result, the symbology can efficiently encode 8-bit bytes for use in computer processing, or encode 16-bit character sets such as Unicode. Symbology encodes extended channel interpretation (ECI) numbers, provides multiple numeric compression modes, provides a structured append using a single mode character, as well as other features.

Claims

1. A method of converting data characters to machine-readable symbols, each symbol having a pattern of dark shapes and light spaces between the shapes, the method comprising:

determining at least first and second character codes corresponding to data characters, wherein each character code has 8 bits;

converting the first and second character codes to first, second and third symbol values;

printing first, second, third symbol characters, wherein the first, second and third symbol characters correspond to the first, second and third symbol values, respectively; and

printing an additional symbol character, wherein the additional symbol character indicates that the first, second and third symbol characters correspond to at least one character code having 8 bits when the combined first, second and third symbol values compute under a formula to a computed value that is less than a predetermined value, and correspond to at least one string of digits if the computed value is greater than the predetermined value.

2. The method of claim 1 wherein printing includes printing first, second and third symbol characters selected from a symbology having three shapes and nine modules per symbol character.

3. The method of claim 1 wherein the acts of determining, converting and printing are repeated for each pair of data characters in a selected string of data characters, wherein each data character has a corresponding 8 bit character code.

4. The method of claim 1, further comprising printing an additional symbol character, wherein the additional symbol character indicates that subsequent symbol characters correspond to at least one 16-bit character code selected from the Unicode standard.

5. The method of claim 1, further comprising:

selecting a first number of digits;

converting the number of digits to a second number of symbol values, the second number being less than the first number;

printing the second number of symbol characters corresponding to the symbol values; and

printing an additional symbol character, wherein the additional symbol character indicates that the second number of symbol characters correspond to digits.

6. The method of claim 1, further comprising:

selecting a number corresponding to preselected data interpretable by a computer;

converting the number to at least one selected symbol value;

printing at least one selected symbol character corresponding to the at least one selected symbol value; and

printing an additional symbol, wherein the additional symbol indicates that the at least one selected symbol corresponds to one of a plurality of predetermined numbers.

7. The method of claim 1, wherein the printing an additional symbol character includes printing symbol characters corresponding to character codes having 8 bits when the computed value is less than approximately 65,536.

8. The method of claim 1 wherein printing an additional symbol character includes printing symbol characters corresponding to four digits when the computed value is between approximately 65,536 and 75,535, and three digits when the computed value is between approximately 75,535 and 76,535.

9. The method of claim 1 wherein the printing an additional symbol character includes computing values under the following formula:

A*43²+B*43+C, where A, B and C correspond to the first, second and third symbol values, respectively, and have values between 0 and 42.

10. A method of converting data characters to machine-readable symbols, each symbol having a pattern of dark shapes and light spaces between the shapes, the method comprising:

determining a plurality of character codes corresponding to a plurality of data characters, respectively;

converting the plurality of character codes to a plurality of symbol values, wherein each of the plurality of symbol values are selected from a set of less than 256 symbol values;

printing a special symbol character; and

printing a plurality of symbol characters, wherein the plurality of symbol characters correspond to the plurality of symbol values, respectively, and wherein the plurality of symbol values correspond to at least one character code having at least 8 bits if a calculated numeric value, for the plurality of symbol values, has a predetermined relationship to at least one predetermined value, and wherein the plurality of symbol values correspond to a string of numeric digits if the calculated value has another predetermined relationship to the predetermined value.

11. The method of claim 10 wherein printing a plurality of symbol characters includes printing symbol characters corresponding to character codes having at least 16 bits when the calculated value is less than approximately 65,536.

12. The method of claim 10 wherein printing the plurality of symbol characters includes printing symbol characters corresponding to two digits when the calculated value is between approximately 76,536 and 76,635.

13. The method of claim 10 wherein the predetermined relationship is a less than relationship, and wherein the another predetermined relationship is a greater than relationship.

14. The method of claim 10 wherein printing includes printing a plurality of symbol characters selected from a symbology having three shapes and nine modules per symbol character.

15. The method of claim 10, further comprising printing an additional symbol character, wherein the additional symbol character indicates that each group of proximate symbol characters correspond to one 16-bit word.

16. The method of claim 10, further comprising:

selecting a first number of digits;

converting the first number of digits to a second number of symbol values, the second number being less than the first number;

printing the second number of symbol characters corresponding to the second number of symbol values; and

printing an additional symbol character, wherein the additional symbol character indicates that at least the second number of symbol characters correspond to digits.

17. The method of claim 10, further comprising:

selecting a number corresponding to preselected data interpretable by a computer;

converting the number to at least one selected symbol value;

printing at least one selected symbol character corresponding to the at least one selected symbol value; and

printing an additional symbol, wherein the additional symbol indicates that the at least one selected symbol corresponds to one of a plurality of predetermined numbers.

18. The method of claim 10, further comprising:

employing a first check character mode if any of the plurality of symbol values have a first range of values;

employing a second check character mode if any of the plurality of symbol values have a second range of values; and

computing at least a first check value under the first or second check character modes based on the plurality of symbol values.

19. The method of claim 10 wherein printing includes printing several symbols selected from a standard bar code symbology.

20. A method of converting data characters to machine-readable symbols, each symbol having a pattern of dark shapes and light spaces between the shapes, the method comprising:

selecting a first number of characters or digits;

converting the first number of characters or digits to a second number of symbol values, the second number being less than the first number; and

printing a number of symbol characters corresponding to the second number of symbol values, wherein groups of two or more of the second number of symbol values provide a computed value under a formula, and wherein the groups of two or more of the second number of symbol values correspond to at least one character if the computed value has a predetermined relationship to a predetermined number, and correspond to compressed numeric digits if the computed value has another predetermined relationship to the predetermined value.

21. The method of claim 20, further comprising:

printing a mode shift symbol character before the printing a number of symbol characters.

22. A method of decoding a bar code label formed on a surface, the method comprising:

imaging the bar code label to produce a signal representative of each of a plurality of symbol characters therefrom;

analyzing the signal to identify the symbol characters; and

converting each symbol character into a corresponding symbol value, wherein each of the plurality of symbol values are selected from a set of less than 256 symbol values, and wherein a group of symbol values, from the plurality of symbol values, together represent at least one character code when the group of symbol values, when computed together, have a predetermined relationship to a predetermined value, and together represent a string of numeric values otherwise.

23. The method of claim 22, further comprising:

identifying a special symbol character before determining that the set of symbol values together represent at least one character code having at least 8 bits.

24. The method of claim 22 wherein the predetermined relationship is a less than relationship.

25. A printer apparatus for printing machine-readable symbols comprising:

a processor that converts a plurality of character codes to a plurality of symbol values, wherein the plurality of character codes correspond to a plurality of data characters, wherein each of the plurality of symbol values are selected from a set of less than 256 symbol values, and wherein a group of symbol values, when computed together to produce a computed value, represent at least one character code having at least 8 bits when the computed value has a predetermined relationship to a predetermined value, and represent a string of numeric values when the computed value has another predetermined relationship to the predetermined value; and

a printer mechanism coupled to the processor that prints a plurality of symbol characters, wherein the plurality of symbol characters correspond to the plurality of symbol values, respectively.

26. The method of claim 25 wherein the processor is configured to generate a flag symbol value when generating a set of symbol values.

27. A reader apparatus for reading machine-readable symbols comprising:

an optical receiver that receives light reflected from a plurality of symbols and produces a signal representing the plurality of symbol characters; and

a processor coupled to the optical receiver that receives the signal and converts the plurality of symbol characters to a plurality of symbol values, wherein each of the plurality of symbol values are selected from a set of less than 256 symbol values, wherein at least one group of the plurality of symbol values correspond to at least one character code having at least 8 bits, when the group of symbol values, computed together, has a predetermined relationship to a predetermined value, and correspond to a string of numeric values when the set of computed symbol values has another predetermined relationship to the predetermined value.

28. The reader apparatus of claim 27 wherein the processor is configured to convert at least one flag symbol character before analyzing a set of symbol values.

29. A method of converting data characters to machine-readable symbols, each symbol having a pattern of dark shapes and light spaces between the shapes, the method comprising:

determining a plurality of character codes corresponding to a plurality of data characters, respectively;

converting the plurality of character codes to a plurality of symbol values, wherein each of the plurality of symbol values are selected from a set of less than 256 symbol values, and wherein groups of a selected number of symbol values selected from the set provide at least first and second ranges of numbers under a predetermined formula; and

printing a plurality of symbol characters, wherein the plurality of symbol characters correspond to the plurality of symbol values, respectively, and wherein one group of the plurality of symbol values corresponds to at least one character code having at least 8 bits if the one group provides a number, under the predetermined formula, within the first range, and wherein the one group corresponds to a string of numeric digits if the one group provides a number, under the predetermined formula, within the second range.