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Touch screen keyboard with self correcting positional capability Disclosure Number: IPCOM000012853D
Original Publication Date: 2003-Jun-03
Included in the Prior Art Database: 2003-Jun-03
Document File: 2 page(s) / 48K

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A method which allows continuous and automatic positional adjustment of a touch screen keyboard is described. Adjustment is controlled through analysis of the coordinates associated with finger hits upon keys on the screen relative to the actual center of the keys on the virtual keyboard. As the location of finger hits relative to the center of keys drifts, the position of the virtual keyboard is moved to compensate.

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Touch screen keyboard with self correcting positional capability

When touch typists try to type on a virtual keyboard that is displayed on a touch screen, errors occur because there is no tactile feedback and no home key cues (such as dots or bars on the F and J keys of a U.S. English key layout) to enable them to maintain correct hand and finger orientation relative to the position of the keys. Various proposals have been made to solve this problem including clear plastic overlays for the screen that provide orientation points, and sensors that would induce a "tingle" in the fingers when keys are hit correctly. The objective of this proposal is different from these previous ideas in that the intent is not to provide cues that allow the user to keep on target, but rather to keep the target located correctly relative to whatever position is adopted by the user.

An overview of the method proposed for this self-positioning virtual keyboard is as follows:

Display a virtual keyboard on a touch screen.

Define the location of each calibrated key (see calibration section below) as an

Store keystrokes and record coordinate location of finger hits on screen.

When a sequence of key strokes that correspond to the calibration string/s is

detected, compare the location of those finger hits against the center coordinates of the corresponding calibrated keys.

If location of finger hit compared to key center coordinates exceeds a

user-defined or pre-defined threshold, move the entire key layout such that the center coordinates of the key will correspond to the actual location of the finger hit. In other words, allow the keyboard to drift over time in accordance with movement of users' hands resulting from the lack of physical or...