SYSTEM FOR IMAGING AND DECODING CODED DATA PATTERN USING REDUNDANTLY-ENCODED ORIENTATION

• US 20110240743A1
• Filed: 06/16/2011
• Published: 10/06/2011
• Est. Priority Date: 12/03/2002
• Status: Active Grant

• Current Assignee: Silverbrook Research Pty Limited
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Lapstun, Paul
• Granted Patent: US 8,215,566 B2
• Time in Patent Office: Days
• US Class Current: 235/468
• 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 system includes a substrate having a coded data pattern disposed on a surface thereof. The coded data pattern encodes a plurality of Reed-Solomon symbols defining tag data and an orientation of a layout of the tag data. An optically imaging sensing device configured for imaging part of the coded data pattern; determining the orientation of the layout of the tag data; and decoding the tag data contained in the imaged part of the coded data pattern.

Claims

1. A system comprising:

(A) 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; and

(B) an optically imaging sensing device configured for;

imaging part of the coded data pattern;

determining the orientation of the layout of the tag data; and

decoding the tag data contained in the imaged part of the coded data pattern.

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

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

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

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

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

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

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

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

10. The system of claim 1, wherein said tag data includes location data identifying a location of a respective tag.

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

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

15. The system of claim 1, wherein said sensing device is comprised of an electronic pen.

16. The system of claim 15, wherein said sensing device is configured for determining a perspective distortion of imaged target features due to a tilt of the pen relative to the surface.