Digital data reader of digital data recording sheet

• US 5,410,620 A
• Filed: 02/09/1993
• Issued: 04/25/1995
• Est. Priority Date: 08/02/1989
• Status: Expired due to Term

• Current Assignee: Teiryo Sangyo Company Limited
• Original Assignee: Teiryo Sangyo Company Limited
• Inventors: Yoshida, Hirokazu
• Primary Examiner(s): Mancuso, Joseph
• Assistant Examiner(s): KLOCINSKI, STEVEN
• Application Number:
  US08/015,087
• Time in Patent Office: 805 Days
• Field of Search: 382/61, 382/46, 382/44, 382/45, 358/470, 358/486, 358/488, 235/494, 235/495, 235/456, 395/117, 395/137
• US Class Current: 382/317
• CPC Class Codes: G06K 7/015 Aligning or centering of the sensing device with respect to the record carrier
• 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 7/1443 locating of the code in an image
• CPC Class Codes: G06K 7/1456 determining the orientation of the optical code with respect to the reader and correcting therefore

Abstract

A system and method for locating and reading digital data in data regions within a data field disposed on a surface of an object to be identified include the capability of compensating for optical or physical distortions of the data field as viewed by an optical reader. The data field is defined by X-axis and Y-axis intersecting basic lines disposed at a predetermined angle with respect to each other and a corner mark disposed on the opposite side of the data field from those basic lines. A plurality of positions marks for marking predetermined distances between a plurality of imaginary X and Y axis internal lines are also provided. The positions of the imaginary X-axis internal lines within the data field are determinable from their spacings and angles with respect to the Y-axis basic line. The positions of the imaginary Y-axis internal lines are determinable from their spacings and their angles with respect to the X-axis basic line. The location of the points of intersection of the imaginary X and Y axis internal lines are calculated in order to define data regions within the data field. The system and method compensate for optical and physical distortions of the locations of the X and Y axis basic lines, corner mark and position marks at the time of reading the data in order to accurately locate positions of the data regions within the data field.

Claims

1. In combination an identification code and reading system therefore, comprising:

the identification code including,

a display area defining a data field including,

an X-axis basic line,

a plurality of X-axis internal line position marks,

a Y-axis basic line, intersecting said X-axis basic line,

a plurality of Y-axis internal line position marks,

a plurality of sub-areas in which encoded indicia are located, and

an additional mark, located such that said display area is defined by an area enclosed by said X-axis basic line, Y-axis basic line and said additional mark; and

the identification code reading system including

display area deciding means for determining a location of said display area on said identification code by determining a location of an X-axis external line and a Y-axis external line disposed on the opposite side of the data field from said X-axis basic line and Y-axis basic lines, respectively,

Y-axis internal line calculating means for determining a location of a plurality of Y-axis internal lines, each passing through one of the plurality of X-axis internal line position marks, said plurality of Y-axis internal lines being equispaced and disposed at angles with respect to the X-axis basic line, the angle of each of said plurality of Y-axis internal lines with respect to said X-axis basic line being;

##EQU10## where;

Θ

_o =an angle formed by the intersection of said X-axis basic line and said Y-axis basic line,

Θ

_x =an angle formed by the intersection of said X-axis basic line and said Y-axis external line,

M_BX =the number of X-axis internal line position marks plus one, and

n=an index used to denote the specific Y-axis internal line being calculated;

X-axis internal line calculating means for determining a location of a plurality of X-axis internal lines, each passing through one of the plurality of Y-axis internal line position marks and disposed at angles with respect to the Y-axis basic line, the plurality of X-axis internal lines being equispaced, said angle of each of said plurality of X-axis internal lines with respect to said Y-axis basic line being;

##EQU11## where;

Θ

_Y =an angle formed by the intersection of said Y-axis basic line and said X-axis external line,

M_BY =the number of Y-axis internal line position marks plus one, and

m=an index used to denote the specific X-axis internal line being calculated;

mark area basic point detecting means for detecting intersections of the plurality of X-axis internal lines and Y-axis internal lines, each intersection forming a mark area basic point,

reading means for reading the plurality of sub-areas in locations determined by the mark area basic points, and

code converting means for converting the encoded indicia in each of the plurality of sub-areas into character information;

whereby optical and physical distortions of the locations of the x and y axis basic lines, corner mark, and position marks are compensated for at the time of reading data in the data field in order to accurately locate positions of the sub-areas within the data field.

2. The combination of claim 1, wherein each mark area basic point is centered on one of the plurality of sub-areas.

3. The combination of claim 1, wherein more than two mark area basic points determine a boundary of each of the plurality of sub-areas.

4. The combination of claim 1,

said identification code reading system further including,

X-axis internal sub-line calculating means for determining a location of a plurality of X-axis internal sub-lines, between each of the plurality of X-axis internal lines, and

Y-axis internal sub-line calculating means for determining a location of a plurality of Y-axis internal sub-lines, between each of the plurality of Y-axis internal lines,

said mark area basic point detecting means further detecting intersections of the plurality of X-axis internal sub-lines and Y-axis internal sub-lines, thereby increasing data density of said identification code.

5. The combination of claim 1, wherein said identification code is in the shape of a parallelogram.

6. The combination of claim 5, wherein said identification code is in the shape of a square.

7. The combination of claim 1, said identification code further including an auxiliary area for locating auxiliary encoded indicia representing auxiliary information,

said additional mark being located such that said display area includes said auxiliary area.

8. A method for reading and processing an identification code, comprising the steps of:

(a) providing the identification code on an object within a data field including,

an X-axis basic line,

a plurality of X-axis internal line position marks,

a Y-axis basic line, intersecting the X-axis basic line,

a plurality of Y-axis internal line position marks,

a plurality of sub-areas in which encoded indicia are located, and

an additional mark, located such that the identification code is defined by an area enclosed by the X-axis basic line, the Y-axis basic line and the additional mark, respectively;

(b) determining a location of the identification code by determining a location of an X-axis external line and a Y-axis external line disposed on the opposite side of the identification code from the X-axis basic line and the Y-axis basic line position marks, respectively;

(c) determining a location of a plurality of Y-axis internal lines, each passing through one of the plurality of X-axis internal line position marks, said plurality of Y-axis internal lines being equispaced and disposed at angles with respect to the X-axis basic line, the angle of each of the plurality of Y-axis internal lines with respect to the X-axis basic line being;

##EQU12## where;

Θ

_o =an angle formed by the intersection of said X-axis basic line and said Y-axis basic line,

Θ

_x =an angle formed by the intersection of said X-axis basic line and said Y-axis external line,

M_BX =the number of X-axis internal line position marks plus one, and

n=an index to denote the specific Y-axis internal line being calculated;

(d) determining a location of a plurality of X-axis internal lines, each passing through one of the plurality of Y-axis internal line position marks, said plurality of X-axis internal lines being equispaced and disposed at angles with respect to the Y-axis basic line, the angle of each of said plurality of X-axis internal lines with respect to said Y-axis basic line being;

##EQU13## where;

Θ

_y =an angle formed by the intersection of said Y-axis basic line and said X-axis external line,

M_BY =the number of Y-axis internal line position marks plus one, and

m=an index to denote the specific X-axis internal line being calculated;

(e) detecting intersections of the plurality of X-axis internal lines and Y-axis internal lines, each intersection forming a mark area basic point;

(f) reading the plurality of sub-areas in locations determined by the mark area basic points; and

(g) converting the encoded indicia in each of the plurality of sub-areas into character information, whereby optical and physical distortions of the locations of the X and Y axis basic lines, corner mark, and position marks are compensated for at the time of reading data in the data field in order to accurately locate positions of the sub-areas within the data field.

9. The method of claim 8, wherein each mark area basic point is centered on one of the plurality of sub-areas.

10. The method of claim 8, wherein more than two mark area basic points determine a boundary of each of the plurality of sub-areas.

11. The method of claim 8, said step (c) further including the sub-step of,

(c)(1) determining a location of a plurality of Y-axis internal sub-lines, between each of the plurality of Y-axis internal lines;

said step (d) further including the sub-step of,

(d)(1) determining a location of a plurality of X-axis internal sub-lines, between each of the plurality of X-axis internal lines; and

said step (e) further including the sub-step of,

(e)(1) detecting intersections of the plurality of X-axis sub-lines and Y-axis internal sub-lines, thereby increasing data density of the identification code.

12. The method of claim 8, wherein the identification code is in the shape of a parallelogram.

13. The method of claim 12, wherein the identification code is in the shape of a square.

14. The method of claim 8, the identification code further including an auxiliary area for locating auxiliary encoded indicia representing auxiliary information.

15. A system for locating and reading digital data in data regions within a data field on a surface and compensating for optical or physical distortions of the data field viewed by an optical reader comprising:

means for defining the data field by providing x-axis and y-axis intersecting basic lines disposed at a predetermined angle with respect to each other and a corner mark on said surface, the corner mark together with the basic lines defining a data field therebetween;

a plurality of position marks for marking predetermined distances between a plurality of imaginary x and y axis internal lines within said data field, said position marks being provided on said surface;

means for defining the positions of a plurality of imaginary x-axis internal lines within said data field, said x-axis internal lines being spaced at predetermined distances from each other defined by the position marks, said x-axis internal lines being disposed at predetermined angles with respect to said y-axis basic line;

means for defining the positions of a plurality of imaginary y-axis internal lines within said data field, said y-axis internal lines being spaced at predetermined distances from each other defined by said position marks, said y-axis internal lines being disposed at predetermined angles with respect to said x-axis basic line;

means for calculating the location of the points of intersection of the imaginary x and y axis internal lines at the time of reading said data from the angle between the x and y axis basic lines, the angles of the x-axis internal lines with respect to the y-axis basic line, the angles of the y-axis internal lines with respect to the x-axis basic line and the location of the position marks;

means for locating said data regions within said data field from the calculated locations of the points of intersection of the x and y axis internal lines at the time of reading; and

means for reading the digital data within said data regions;

whereby optical and physical distortions of the locations of the x and y axis basic lines, corner mark and position marks are compensated for at the time of reading the data in order to accurately locate positions of the data regions within the data field.

16. The system of claim 15, said means for defining the data field further providing an X-axis external line and a Y-axis external line disposed on the opposite side of the data field from said X-axis and y-axis intersecting basic lines, respectively, for further defining the data field therebetween.

17. A method for locating and reading digital data in data regions within a data field on a surface and compensating for optical or physical distortions of the data field viewed by an optical reader, comprising the steps of:

defining the data field by providing x-axis and y-axis intersecting basic lines disposed at a predetermined angle with respect to each other and a corner mark on said surface, the corner mark together with the basic lines defining a data field therebetween;

marking predetermined distances between a plurality of imaginary x and y axis internal lines within said data field with position marks, said position marks being provided on said surface;

defining the positions of a plurality of imaginary x-axis internal lines within said data field, said x-axis internal lines being spaced at predetermined distances from each other defined by the position marks, said x-axis internal lines being disposed at predetermined angles with respect to said y-axis basic line;

defining the positions of a plurality of imaginary y-axis internal lines within said data field, said y-axis internal lines being spaced at predetermined distances from each other defined by said position marks, said y-axis internal lines being disposed at predetermined angles with respect to said x-axis basic line;

calculating the location of the points of intersection of the imaginary x and y axis internal lines at the time of reading said data from the angle between the x and y axis basic lines, the angles of the x-axis internal lines with respect to the y-axis basic line, the angles of the y-axis internal lines with respect to the x-axis basic line and the location of the position marks;

locating said data regions within said data field from the calculated locations of the points of intersection of the x and y axis internal lines at the time of reading; and

reading the digital data within said data regions;

whereby optical and physical distortions of the locations of the x and y axis basic lines, corner mark and position marks are compensated for at the time of reading the data in order to accurately locate positions of the data regions within the data field.

18. The method of claim 17, wherein the step of defining the data field further includes providing an X-axis external line and a Y-axis external line disposed on the opposite side of the data field from said X-axis and Y-axis intersecting basic lines, respectively, for further defining the data field therebetween.