System and method for determining positional information

• US 6,689,966 B2
• Filed: 03/21/2001
• Issued: 02/10/2004
• Est. Priority Date: 03/21/2000
• Status: Expired due to Fees

• Current Assignee: Anoto Group AB
• Original Assignee: Anoto Group AB
• Inventors: Wiebe, Linus
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Tran, Henry N.
• Application Number:
  US09/812,900
• Publication Number:
  US 20020021284A1
• Time in Patent Office: 1,056 Days
• Field of Search: 345/156-158, 345/162, 345/163, 345/165, 345/166, 345/173, 345/175, 345/179, 178/18.01, 178/18.03, 178/18.09, 178/19.01, 178/19.05, 235/494, 235/454-456, 382/181-184, 382/188, 382/299, 382/201, 382/312-314, 382/317
• US Class Current: 178/18.01
• CPC Class Codes: G06F 3/0321 by optically sensing the absolute position with respect to a regularly patterned surface forming a passive digitiser, e.g. pen optically detecting position indicative tags printed on a paper sheet constructional details of pen-shaped pointing devices G06F3/03545, G06F3/03542, G06F3/037
• CPC Class Codes: G06F 3/03545 Pens or stylus
• 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: G06V 10/17 using hand-held instruments
• CPC Class Codes: G06V 10/19 by sensing codes defining pattern positions

Abstract

A product has a surface having with a position-coding pattern that codes a plurality of positions on the surface. The position-coding pattern includes a plurality of symbols each having at least two different values. Each position on the surface being coded with a plurality of symbols. Each symbol including a raster point in a raster extending over the surface, and at least one marking, the location of which in relation to the raster point specifies the value of the symbol. The markings can include information representing more than one spatial resolution level and varying between different markings. The position-coding pattern can be used in different contexts for position determination such as digitizing handwriting.

Claims

1. A product comprising:

a surface having a coding pattern for position determination, wherein the coding pattern includes symbols representing at least two different values,

wherein each symbol includes a raster point and at least one marking, wherein the raster point is included in a raster extending over the surface, and wherein the location of the marking in relation to a raster point determines a value of each symbol; and

at least one marking having marking information, wherein the markings in the coding pattern at a first spatial resolution level are substantially identical to each other, wherein at least one marking in a second spatial resolution level is different than the first level, and wherein the second level has a higher resolution than the first level.

2. A product according to claim 1, wherein the coding pattern is a position-coding pattern that codes a plurality of positions on the surface, each position being coded by a plurality of symbols.

3. A product according to claim 2, wherein each symbol contributes to the coding of more than one of said plurality of positions.

4. A product according to claim 3, wherein each symbol contributes to the coding of both a first and a second position coordinate.

5. A product according to claim 4, wherein the value of each symbol is translatable into at least a first digit for coding the first position coordinate and at least a second digit for coding the second position coordinate, and wherein the symbols in the position-coding pattern together represent a first position code and a second position code.

6. A product according to claim 5, wherein the position-coding pattern is based on a first cyclic number series, and wherein no sequence with a first predetermined number of digits occurs more than once in the number series.

7. A product according to claim 5, wherein the first coordinate is coded by a first cyclic number series, wherein no sequence with a first predetermined number of digits occurs more than once in the number series, wherein the series is repeated in columns over the surface, and wherein the columns begin at different locations in the number series.

8. A product according to claim 7, wherein the second coordinate is coded by a second cyclic number series, wherein no sequence with a second predetermined number of digits occurs more than once in the number series, wherein the series is repeated in columns over the surface, and wherein the columns begin at different locations in the number series.

9. A product according to claim 8, wherein the product comprises a plurality of writing surfaces, each including the position-coding pattern, the position-coding patterns differing for the different writing surfaces by the sequence in the cyclic number series with which a predetermined column or row begins.

10. A product according to claim 9, wherein the raster and the raster point are virtual.

11. A product according to claim 1, wherein each symbol has at least one marking that can be placed in one of four predetermined positions on the lines of the raster so that the symbol has at least four values.

12. A product according to claim 1, wherein the marking information is coded as a pattern varying in a binary manner.

13. A product according to claim 1, wherein the coding pattern is optically read.

14. A program, stored on a computer-readable medium, for determining a position of a partial surface on a principle surface having a position-coding pattern comprised of a plurality of symbols, wherein each symbol includes a raster point and at least one marking, said program comprising instructions for

locating a predetermined plurality of symbols in an image of the partial surface;

determining the value of each said predetermined plurality of symbols;

separating the position-coding pattern into a first position code for a first coordinate of the partial surface and a second position code for a second coordinate of the partial surface by translating the value of each symbol into at least a first digit for the first position code and at least a second digit for the second position code;

calculating the first coordinate using the first position code and the second coordinate using the second position code;

calculating the value of each symbol by determining the location of each marking in relation to the raster point, wherein each symbol has at least one marking in one of four predetermined positions on the lines of the raster so that the symbol has at least four values;

locating at least one marking having marking information; and

interpreting the marking information.

15. A system comprising:

a sensor configured to detect an image from a partial surface of a plurality of partial surfaces on a principle surface, wherein the partial surface includes a position-coding pattern, and

an image-processing element configured to;

locate a predetermined plurality of symbols in the image, wherein each symbol includes at least one marking;

determine the value of each of said predetermined plurality of symbols;

separate the position-coding pattern in the image into a first position code for a first coordinate for the partial surface and into a second position code for a second coordinate for the partial surface by translating the value of each symbol into at least a first digit for the first code and at least a second digit for the second code;

calculate the first coordinate using the first position code and the second coordinate using the second position code;

locate at least one marking which comprises marking information; and

interpret the marking information, wherein the marking information is coded as a pattern varying in a binary manner.

16. A system according to claim 15, wherein the sensor is handheld.

17. A system according to claim 16, wherein the sensor further includes

a transceiver configured to communicated the detected image via wireless transmission.

18. A system comprising:

a sensor configured to produce an image of a partial surface from a plurality of partial surfaces on a product, wherein each partial surface includes a position-coding pattern, wherein the position-coding pattern includes a plurality of symbols, wherein each symbol includes a raster point and at least one marking; and

a program, stored on a computer-readable medium and in communication with the sensor, the program including instructions to;

locate a predetermined plurality of symbols in the image of the partial surface;

determine the value of each said predetermined plurality of symbols;

separate the position-coding pattern into a first position code for a first coordinate of the partial surface and a second position code for a second coordinate of the partial surface by translating the value of each symbol into at least a first digit for the first position code and at least a second digit for the second position code;

calculate the first coordinate using the first position code and the second coordinate using the second position code;

calculate the value of each symbol by determining a location of each marking in relation to the raster point;

locate at least one marking having marking information; and

interpret the marking information.

19. A method for determining the position of a partial surface on a principle surface having a position-coding pattern that includes a plurality of symbols, wherein each symbol includes a raster point and at least one marking, said method comprising:

locating a predetermined plurality of symbols in an image of the partial surface;

determining the value of each said predetermined plurality of symbols;

separating the position-coding pattern into a first position code for a first coordinate of the partial surface and a second position code for a second coordinate of the partial surface by translating the value of each symbol into at least a first digit for the first position code and at least a second digit for the second position code;

calculating the first coordinate using the first position code and the second coordinate using the second position code;

calculating the value of each symbol by determining the location of each marking in relation to the raster point;

locating at least one marking having marking information; and

interpreting the marking information.