Method and apparatus for recording digital information in two-dimensional pattern, carrier of digital information recorded thereby, and a method and apparatus for decoding such digital information

• US 6,302,329 B1
• Filed: 12/26/1995
• Issued: 10/16/2001
• Est. Priority Date: 12/27/1994
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Iwai, Toshiyuki, Aoki, Atsushi, Kaminokado, Tsukasa, Niwamoto, Hiroaki, Esashi, Masahiro, Yamaguchi, Norimasa
• Primary Examiner(s): TREMBLAY, MARK STEPHEN
• Application Number:
  US08/578,502
• Time in Patent Office: 2,121 Days
• Field of Search: 235/487, 235/494, 235/456, 235/462.08, 235/462.09
• US Class Current: 235/494
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1417 2D bar codes

Abstract

A digital information recording carrier has a planar recording surface having an information recording area in which meshes corresponding to bits are virtually set in a matrix form, each mesh being provided with an optically recognizable mark corresponding to digital information so that the digital information is recorded in the information recording area as a two-dimensional pattern. The carrier also has specific patterns each consisting of a plurality of meshes which are linked together and which are given marks in a given pattern. Some of the specific patterns are placed in an inner portion apart from a perimeter of the information recording area.

Claims

1. A digital information recording carrier, comprising:

a planar recording surface having an information recording area, said information recording area defining a plurality of cells arranged in matrix form,

each said cell being provided with an optically recognizable mark such that said cells together form an optically readable, two-dimensional pattern filling said information recording area;

said two-dimensional pattern comprising first portions wherein said cells respectively correspond to bits of digital information and second portions wherein said cells correspond to specific patterns that are spaced from each other, each said specific pattern consisting of a plurality of cells which are linked together and which are given optically recognizable marks in a respective pre-selected pattern, said specific patterns including a predetermined pattern which occupies a region in an inner portion of said information recording area spaced from a perimeter of said information recording area, said predetermined pattern including at least one central cell representing a first value and a plurality of contiguous cells representing a second value and at least partially surrounding said central cell; and

said first portions of said information recording area occupy all regions of said information recording area other than the regions occupied by said specific patterns;

further wherein the cells which make up the predetermined pattern are the same size and shape as the cells which make up the first portions of said information recording area.

2. The digital information recording carrier according to claim 1, wherein said specific patterns are dispersedly arranged all over the information recording area.

3. The digital information recording carrier according to claim 1, wherein

said cells each have the shape of a square and identical size, wherein

each specific pattern is composed of a central closed areas with the shape of a square, and a loop portion entirely surrounding the central closed area, and wherein

said central closed area consists of four cells, each provided with a light optically recognizable mark and said loop portion consists of twelve cells, each provided with a dark optically recognizable mark.

4. The digital information recording carrier according to claim 1, wherein

said cells each have the shape of a square and identical size, wherein each specific pattern is composed of a central portion with the shape of a square, a first loop portion entirely surrounding the central portion, and a second loop portion entirely surrounding the first loop portion;

and

wherein said central portion consists of a single cell provided with a dark optically recognizable mark, said first loop portion consists of eight cells each provided with a light optically recognizable mark, and said second loop portion consists of sixteen cells each provided with a dark optically recognizable mark.

5. The digital information recording carrier according to claim 2, wherein

said information recording area is a rectangular area having two first sides extending in a first direction and two second sides extending in a second direction perpendicular to the first direction;

said specific patterns are arranged at intervals along said first and second directions;

the intervals between said specific patterns arranged along said first direction are smaller in areas near said second sides than in areas far from said second sides; and

the intervals between said specific patterns arranged along said second direction are smaller in areas near said first sides than in areas far from said first sides.

6. The digital information recording carrier according to claim 2, wherein

said information recording area is a rectangular area having two first sides extending in a first direction and two second sides extending in a second direction perpendicular to the first direction;

said specific patterns are arranged at intervals along said first and second directions;

the intervals between said specific patterns arranged along said first direction are larger in areas near said second sides than in areas far from said second sides; and

the intervals between said specific patterns arranged along said second direction are larger in areas near said first sides than in areas far from said first sides.

7. The digital information recording carrier according to claim 2, wherein said information recording area is a rectangular area having four corners and a specific pattern is placed at each corner.

8. The digital information recording carrier according to claim 7, wherein the specific patterns placed at the four corners are different from the specific patterns placed in the other portions of the information recording area.

9. The digital information recording carrier according to claim 7, wherein part of the specific patterns placed at the four corners are different from the rest thereof such that a set of the specific patterns placed at the four corners becomes asymmetrical with respect to a 90°

, 180°

, or 270°

rotation on the recording surface.

10. The digital information recording carrier according to claim 1, wherein

said specific patterns have light and dark as the optically recognizable marks, and wherein

a light/dark status of some of said specific patterns is inverse to that of the other specific patterns, so as to make a contrast against cells on which said specific patterns abut and in which digital information has been recorded.

14. A digital information recording carrier according to claim 1, wherein

one of said first and second values is binary zero and the other of said first and second values is binary one.

15. A digital information recording carrier according to claim 1, wherein

said plurality of contiguous cells forms a loop completely surrounding said central cell.

11. A digital information recording method, comprising the steps of:

providing a planar recording surface having an information recording area, said information recording area defining a plurality of cells arranged in matrix form,

providing each said cell with an optically recognizable mark such that said cells together form an optically readable, two-dimensional pattern filling said information recording area;

said two-dimensional pattern comprising first portions wherein said cells respectively correspond to bits of digital information and second portions wherein said cells correspond to specific patterns that are spaced from each other, each said specific pattern consisting of a plurality of cells which are linked together and which are given optically recognizable marks in a respective pre-selected pattern;

locating at least a predetermined one of said specific patterns in a region in an inner portion of said information recording area spaced from a perimeter of said information recording area, said predetermined pattern including at least one central cell representing a first value and a plurality of contiguous cells representing a second value and at least partially surrounding said central cell; and

filling all regions of said information recording area other than the regions occupied by said specific patterns with digital information containing cells;

wherein the cells which make up the predetermined pattern are the same size and shape as the cells which make up the first portions of said information recording area.

12. The digital information recording method according to claim 11, wherein each mark represents either a light or a dark, the method further comprising the steps of:

comparing light/dark statuses of cells defining a perimeter of each specific pattern with light/dark statuses of information-recorded cells which are immediately adjacent to the perimeter of the specific pattern; and

inverting, if the compared light/dark statuses are coincident with each other, the light/dark statuses of constituent cells of the specific pattern such that the specific pattern is distinguished from the adjacent information-recorded cells.

13. A digital information recording apparatus for recording digital information as a portion of a two-dimensional pattern filling an information recording area provided on a planar recording surface, wherein

cells each having the same size and shape are defined in a matrix form in the information recording area, and

the recording of digital information is executed by providing an optically recognizable mark, corresponding to the digital information, at each of the cells and providing at an inner portion of said information recording area specific patterns of cells, said specific patterns of cells including a predetermined pattern, said predetermined pattern including at least one central cell representing a first value and a plurality of contiguous cells representing a second value and at least partially surrounding said central cell, said digital information recording apparatus comprising:

input means for inputting digital information to be recorded into the digital information recording apparatus;

pattern generating means for generating a two-dimensional pattern of cells having the same size and shape to be printed onto said information recording area of said recording surface, by placing specific patterns of said cells within and spaced from the perimeter of the information recording area to be printed, the specific patterns being each formed of a plurality of contiguous cells provided with optically recognizable marks in a respective pre-selected pattern, and by placing digital information in all regions of the two-dimensional pattern to be printed in the information recording area other than the regions occupied by the specific patterns by encoding the cells located therein with optically recognizable marks respectively corresponding to bits of said digital information; and

printing means for printing the two-dimensional pattern generated by the pattern generating means onto the recording surface.

16. A digital information recording carrier, comprising:

a planar recording surface having an information recording area in which cells are defined in a matrix form, each cell being provided with an optically recognizable mark so that a two-dimensional pattern filling the information recording area is formed;

wherein said two-dimensional pattern includes specific patterns, each consisting of a plurality of cells which are linked together and which are given optically recognizable marks in respective pre-selected patterns, said specific patterns including a predetermined pattern which is placed in an inner portion of said information recording area, spaced from a perimeter of said information recording area, said predetermined pattern including at least one central cell representing a first value and a plurality of contiguous cells representing a second value and at least partially surrounding said central cell,

wherein said specific patterns are spaced from each other, and said information recording area comprises first data areas of a polygonal shape at comers of which said specific patterns are disposed, respectively, and second data areas which are disposed along sides of each first data area and between said specific patterns and which are continuous both with said first data areas and with said specific patterns, said first and second data areas containing the digital information to be read; and

wherein the cells contained in said first and second data areas are the same size and shape as the cells making up said specific patterns.

17. A digital information recording method, comprising the steps of:

defining cells in a matrix form filling an information recording area provided within a planar recording surface;

placing specific patterns at least in an interior of the information recording area, said specific patterns being spaced from each other and from a perimeter of the information recording area, wherein each specific pattern consists of a plurality of cells which are linked together and which are given optically recognizable marks in a pre-selected respective pattern, wherein said specific patterns placed in the interior, and spaced from the perimeter of the information recording area, include a predetermined pattern having at least one central cell representing a first value and a plurality of contiguous cells representing a second value and at least partially surrounding said central cell; and

providing each of the cells present in regions of the information recording area other than regions thereof occupied by the specific patterns with an optically recognizable mark corresponding to digital information to be recorded so that the digital information is recorded in the information recording area as a two-dimensional pattern,

wherein, after the digital information has been recorded, said information recording area comprises first data areas of a polygonal shape at corners of which said specific patterns are disposed, respectively, and second data areas which are disposed along sides of each first data area and between said specific patterns and which are continuous both with said first data areas and with said specific patterns, said first and second data areas containing said digital information, and

wherein the cells contained in said first and second data areas are the same size and shape as the cells making up said specific patterns.

18. A digital information recording apparatus for recording a two-dimensional pattern filling an information recording area provided within a planar recording surface, wherein

cells define a matrix form in the information recording area, and

recording of digital information is executed by providing an optically recognizable mark, corresponding to the digital information, at each of selected ones of the cells, and providing at an inner portion of said information recording area specific patterns of cells, said specific patterns including a predetermined pattern of cells, said predetermined pattern including at least one central cell representing a first value and a plurality of contiguous cells representing a second value and at least partially surrounding said central cell, said digital information recording apparatus comprising:

input means for inputting digital information to be recorded into the digital information recording apparatus;

pattern-generating means for generating a two-dimensional pattern to be printed onto the recording surface, by placing specific patterns inside of the information recording area, spaced from its perimeter and each other, the specific patterns being each formed of a plurality of contiguous cells provided with optically recognizable marks in a respective pre-selected pattern, and by placing the digital information in cells of the same size and shape as the cells forming each of the specific patterns in regions of the information recording area, other than regions occupied by the specific patterns; and

printing means for printing the two-dimensional pattern, generated by the pattern-generating means, onto the recording surface such that after the two-dimensional pattern has been printed on the recording surface, said information recording area comprises first data areas of a polygonal shape at corners of which said specific patterns are disposed, respectively, and second data areas which are disposed along sides of each first data area and between said specific patterns and which are continuous both with said first data areas and with said specific patterns, said first and second data areas containing said digital information to be read.

19. A method of recording optically recognizable digital information within a polygonal region on a planar recording surface, which region comprises a multiplicity of polygonal cells filling said polygonal region, said method comprising:

distributing over said region and spaced from each other, a plurality of predetermined reference patterns, each of which comprises a plurality of said cells, there being both reference patterns residing within each corner of said polygonal region and also a plurality of reference patterns distributed over said polygonal region spaced from the perimeter thereof; and

recording within those of said cells not occupied by said predetermined reference patterns, digital information which is to be optically readable,

wherein the cells which make up the predetermined reference patterns are the same size and shape as the cells which are used to record the digital information.

20. The method as set forth in claim 19, wherein said predetermined patterns comprise at least one central cell representing a first binary value and a plurality of contiguous cells at least partially surrounding said central cell and representing a second binary value.

21. The method as set forth in claim 20, wherein said region is rectangular and said cells are essentially square shaped.

22. A method of recording optically recognizable digital information within a rectangular region on a planar recording surface, which region comprises a multiplicity of essentially identical square cells, said method comprising:

distributing over said region and spaced from each other, a plurality of predetermined reference patterns each of which comprises a plurality of said cells, said predetermined reference patterns comprising at least one central cell representing a first binary value and a plurality of contiguous cells at least partially surrounding said central cell and representing a second binary value, there being both reference patterns residing within each corner of said rectangular region and also a plurality of reference patterns distributed over said rectangular region spaced from the perimeter thereof, there being still further reference patterns adjacent the borders of the longer sides of said rectangular region and spaced from the corners of said region; and

recording within those of said cells not occupied by said predetermined reference patterns, optically readable digital information.

23. A digital information recording carrier, comprising:

an information recording area on a recording surface of the carrier, which area comprises a continuous data recording area and one or more mutually spaced first pattern areas, wherein

said data recording area consists of a multiplicity of cells, said cells representing optically readable digital data;

said one or each first pattern area consists of a plurality of cells, said cells representing an optically readable specific pattern used for compensating deviations of positions of the cells in said data recording area; and

said one or each first pattern area is entirely encompassed by said continuous data recording area such that no gap exists between said data recording area and said one or each first pattern area.

24. The digital information recording carrier according to claim 23,

wherein said information recording area further comprises second patterns areas outside of said data recording area, said second pattern areas being spaced from said one or each first pattern area and from each other, each second pattern area consists of a plurality of cells representing an optically readable specific pattern, and no gap exists between said data recording area and each second pattern area.

25. The digital information recording carrier according to claim 23, wherein said optically readable specific pattern comprises at least one central cell representing a first binary value and a plurality of contiguous cells completely surrounding said at least one central cell and representing a second binary value.

26. The digital information recording carrier according to claim 23,

wherein said optically readable specific pattern comprises at least one central cell representing a first binary value, a plurality of first contiguous cells completely surrounding said at least one central cell and representing a second binary value, and a plurality of second contiguous cells completely surrounding said plurality of first contiguous cells and representing said first binary value.

27. The digital information recording carrier according to claim 25,

wherein said at least one central cell has a light color and said contiguous cells have a dark color.

28. The digital information recording carrier according to claim 26,

wherein said at least one central cell has a dark color, said first contiguous cells have a light color, and said second contiguous cells have a dark color.