摘要 |
A transparent capacitive surface (1) is supported at its corners by flexible leaf blades (1A-1D) on which strain gauges are mounted. A high frequency supply (2) is connected to a series capacitor (3) and a multiplexer is linked to the four corner connections. A connection is made to a detection circuit (6) and a computer (9). The corners of the capacitive surface are connected in turn to the high frequency voltage supply, and the voltages read from these corners are compared with a table of values in order to determine the point at which the capacitive surface is being touched.
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