06323846 is referenced by 2079 patents and cites 22 patents.

Apparatus and methods are disclosed for simultaneously tracking multiple finger and palm contacts as hands approach, touch, and slide across a proximity-sensing, compliant, and flexible multi-touch surface. The surface consists of compressible cushion, dielectric, electrode, and circuitry layers. A simple proximity transduction circuit is placed under each electrode to maximize signal-to-noise ratio and to reduce wiring complexity. Such distributed transduction circuitry is economical for large surfaces when implemented with thin-film transistor techniques. Scanning and signal offset removal on an electrode array produces low-noise proximity images. Segmentation processing of each proximity image constructs a group of electrodes corresponding to each distinguishable contact and extracts shape, position and surface proximity features for each group. Groups in successive images which correspond to the same hand contact are linked by a persistent path tracker which also detects individual contact touchdown and liftoff. Combinatorial optimization modules associate each contact's path with a particular fingertip, thumb, or palm of either hand on the basis of biomechanical constraints and contact features. Classification of intuitive hand configurations and motions enables unprecedented integration of typing, resting, pointing, scrolling, 3D manipulation, and handwriting into a versatile, ergonomic computer input device.

Title
Method and apparatus for integrating manual input
Application Number
9/236513
Publication Number
6323846 (B1)
Application Date
January 25, 1999
Publication Date
November 27, 2001
Inventor
John G Elias
Townsend
DE, US
Wayne Westerman
Wellington
MO, US
Agent
Connolly Bove Lodge & Hutz
US
Assignee
University of Delaware
DE, US
IPC
G09G 5/00
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