Coded data pattern having redundantly-encoded orientation

• US 7,984,858 B2
• Filed: 05/31/2009
• Issued: 07/26/2011
• Est. Priority Date: 12/03/2002
• Status: Expired due to Fees

• Current Assignee: Silverbrook Research Pty Limited
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Lapstun, Paul
• Primary Examiner(s): Le; Thien M.
• Assistant Examiner(s): Taylor; April A
• Application Number:
  US12/475,554
• Publication Number:
  US 20090236427A1
• Time in Patent Office: 786 Days
• Field of Search: 235/375, 235/487, 235/494, 235/454, 235/462.01, 235/472.01
• US Class Current: 235/494
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/10871 randomly oriented data-fields, code-marks therefore, e.g. concentric circles-code

Abstract

A substrate having a coded data pattern disposed on a surface thereof. The coded data pattern comprises a plurality of target features defining a grid. The grid comprises a plurality of tags with neighboring tags sharing target features. Each tag comprises respective tag data encoded by a plurality of macrodot data elements contained in each tag. The macrodot data elements encode: a plurality of Reed-Solomon symbols, wherein a set of the symbols define a Reed-Solomon codeword; and an orientation of a layout of the tag data. The orientation is encoded a plurality of times in each tag.

Claims

1. A substrate having a coded data pattern disposed on a surface thereof, said coded data pattern comprising a plurality of discrete circular target features defining a grid, said grid comprising a plurality of tags with neighboring tags sharing target features, each tag comprising respective tag data encoded by a plurality of macrodot data elements contained in each tag, wherein said macrodot data elements encode:

a plurality of Reed-Solomon symbols, wherein a set of said symbols define a Reed-Solomon codeword representing at least some of said tag data; and

an orientation of a layout of said tag data,

wherein said orientation is encoded a plurality of times in each tag.

2. The substrate of claim 1, wherein each tag comprises at least four target features.

3. The substrate of claim 1, wherein said grid is a square grid comprising a plurality of square tags.

4. The substrate of claim 3, wherein each square tag comprises target features positioned at respective corners thereof.

5. The substrate of claim 1, wherein each Reed-Solomon symbol is a multi-bit symbol encoded by a group of macrodot data elements.

6. The substrate of claim 1, wherein said coded data pattern is printed onto the substrate.

7. The substrate of claim 1, wherein said coded data pattern is printed with an infra-red ink.

8. The substrate of claim 1, wherein said coded data pattern has low-visibility or is invisible to an average unaided human eye.

9. The substrate of claim 1, wherein at least some of said coded data pattern is printed coincident with human-readable visible markings.

10. The substrate of claim 1, wherein said tag data includes location data identifying a location of a respective tag with respect to a region of said surface.

11. The substrate of claim 10, wherein said location data is represented by at least one Reed-Solomon codeword.

12. The substrate of claim 1, wherein said tag data includes region data identifying a region of said surface within which said coded data pattern is disposed.

13. The substrate of claim 12, wherein said region of said surface corresponds to the whole surface.

14. The substrate of claim 1, which is paper, card or another laminar medium.