05051736 is referenced by 912 patents and cites 12 patents.

A stylus and table X-Y data input system for a video display system. The pen includes an optical styling having a suitable pickup mechanism and the tablet is passive in nature and provides direct digitized data readout. Absolute positional information is encoded in binary form in the tablet in such a fashion that the pen position upon the tablet is automatically determinable by illuminating a particular area of the tablet and reading off the digitized X-Y coordinate data stored therein. The pen and supporting hardware/software are rotationally insensitive so that the pen may be held in any desired position comfortable to a user. The system provides greatly improved resolution, sampling rate accuracy and general robustness particularly for such applications as text recognition as well as a wide variety of other graphical input uses.

Title
Optical stylus and passive digitizing tablet data input system
Application Number
7/373298
Publication Number
5051736
Application Date
June 28, 1989
Publication Date
September 24, 1991
Inventor
Todd K Rodgers
Chappaqua
NY, US
Karl Friedrich Etzold
Briarcliff Manor
NY, US
Anthony R Davies
Romsey
GB
Stephen J Boies
Mahopac
NY, US
William E Bennett
Mahopac
NY, US
Agent
Roy R Schlemmer
Assignee
International Business Machines Corporation
NY, US
IPC
G06K 9/00
G08C 21/00
G09G 1/28
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