Data storage device incorporating a two-dimensional code

1 . A data storage device which comprises

a data carrier having at least one planar surface; and

an array of detectable items positioned on the planar surface and detectable with a sensing device, the array being configured to represent a two-dimensional code that defines at least executable instructions and redundancy encoding to impart fault tolerant characteristics to the code, the executable instructions including image processing algorithms.

2 . A data storage device as claimed in claim 1 , in which the data carrier is a card such that the array of detectable items are positioned on a first surface of the card and a visual depiction representing the code is positioned on a second opposite surface of the card.

3 . A data storage device as claimed in claim 2 , in which the card is of a plastics material that is coated with a hydrophilic dye-fixing layer.

4 . A data storage device as claimed in claim 2 , in which the detectable items are in the form of dots printed on the first surface of the card.

5 . A data storage device as claimed in claim 4 , in which the redundancy encoding includes reed-solomon fault correction encoding.

6 . A data storage device as claimed in claim 4 in which the array of dots are printed with a 1600 dpi resolution.

7 . A data storage device as claimed in claim 4 , in which the dots define at least one target which is detectable by the sensor, the target being associated with at least one data area defined by the dots.

8 . A data storage device as claimed in claim 7 , in which the targets are oriented to permit reading of the card in at least two directions.