摘要 |
Capacitive touch screens are subject to a "handshadow' error associated with the undesired proximity detection of a portion of a relatively large object (such as a hand) comprising or associated with a smaller pointing portion or object (such as finger tip), where the smaller pointing portion is closer to a touch sensing surface than is the rest of the object. A history profile of data derived from the screen both just prior to, and just after the touch is detected can be processed to compensate for the handshadow effect and to determine a corrected touch position value based on regression techniques or other forms of predictive mathematics. In addition to accurately determining positions where a screen is touched, these approaches can also determine a screen location corresponding to a position of closest approach of a pointing object. A system for providing the handshadow-compensated measurements may comprise a memory for storing a temporal sequence of touch screen records and a computer for executing several algorithms.
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