US Patent 7330590 Pen out-of-proximity handwriting-recognition trigger

In a computer system that accepts handwritten input, a digitizer tracks the location of a user's pen while the pen is not in contact with the digitizer's writing surface. The digitizer maps the pen's three-dimensional location into a two-dimensional location on the digitizer's writing surface. Handwriting-recognition is triggered for handwriting entered into a handwriting-recognition task area upon detecting that the user has lifted the pen off of the digitizer's writing surface and that the pen has moved out of proximity from the handwriting-recognition task area. The handwriting-recognition triggering may be inhibited when the pen is down and in contact with the digitizer's writing surface in an inking orientation.