| US 7,542,607 B2 | ||
| Digital pen and paper | ||
| Emiliano Bartolome, Pontevedra (Spain) | ||
| Assigned to Hewlett-Packard Development Company, L.P., Houston, Tex. (US) | ||
| Filed on Apr. 21, 2005, as Appl. No. 11/110,775. | ||
| Claims priority of application No. 0409417.3 (GB), filed on Apr. 28, 2004. | ||
| Prior Publication US 2005/0249415 A1, Nov. 10, 2005 | ||
| Int. Cl. G06K 9/00 (2006.01); G06K 9/46 (2006.01) | ||
| U.S. Cl. 382—187 [382/188; 382/203] | 20 Claims |
| 1. A digital pen and paper system comprising a pen arranged to make pen strokes on a document having a plurality of regions, to detect markings on the document, and to record them in a series of samples, wherein: the system is arranged to determine from the samples the position of the pen strokes; the system has defined therein a plurality of different warning conditions that determine when a warning will be produced in response to lost samples; and the system is arranged to select one of the warning conditions for one of the pen strokes depending on which of the regions the pen stroke is made in. |