08970540 is referenced by 12 patents and cites 52 patents.

An electronic device has a marking surface overlaid on a touch sensor. Marks made upon the marking surface create pressure that is transferred through the thickness of the marking surface to the touch sensor. Thus, the signals detected by the touch sensor correspond to the marks made on the marking surface. The marking surface may include a thin material that displays marks such as a pressure-sensitive cholesteric liquid crystal display or a conventional sheet of paper. The touch sensor may comprise a sensor capable of detecting an amount of incident force such as an interpolating force-sensitive resistance touch sensor. The electronic device may also have hardware and/or software to analyze the marks detected by the touch sensor and to communicate with other electronic devices.

Title
Memo pad
Application Number
12/890318
Publication Number
8970540 (B1)
Application Date
September 24, 2010
Publication Date
March 3, 2015
Inventor
Amish Rajesh Babu
Sunnyvale
CA, US
Joseph J Hebenstreit
San Francisco
CA, US
Agent
Lee & Hayes PLLC
Assignee
Amazon Technologies
WA, US
IPC
G06F 3/045
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