2019.1

Pattern sizes
The absolute minimum required for an Anoto Digital Pen to read the pattern and know it's
position on the page is 7mm (1/4"). Any pattern smaller than this will not be readable. However,
at 7mm width and height, the pen can only recognize a single dot within that pattern, at the top
of the field.
This is because the pen's camera (which captures the position of the pen) is located under the
pen tip and must fully see the pattern. The following image illustrates how the pen reads its
position:
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