| 摘要 |
<p>A system providing greater accuracy of touch location and better rejection of noise comprises a plurality of force sensing detectors (50) for detecting and generating electrical signals proportional to the applied touch. Alternating current coupling circuits (508) reshape the electrical signals from each detector for accentuating the common dynamic frequency characteristics of the variety of forces presented to the system. A sample collection circuit (511) sequentially collects samples (401a) from each AC coupling circuit (508a) until a predeytermined interval of time lapses (402) or until the second zero crossing (403) of one electrical signal simple is detected, whichever event occurs first. Samples are averaged before calculating the location of the touching force. An average reference level for each force sensing device is established prior to the collection of the force samples to automatically adjust for any changes in the condition of the system. (Fig. 5)</p> |
